{"gene":"CIB1","run_date":"2026-04-28T17:28:52","timeline":{"discoveries":[{"year":2004,"finding":"Crystal structure of Ca2+-bound CIB1 determined at 2.0 Å resolution, revealing a compact alpha-helical protein with four EF-hands (last two bind calcium), structural similarity to calcineurin B and neuronal calcium sensor (NCS) proteins, and a conserved hydrophobic pocket implicated in ligand binding; mutagenesis confirmed the hydrophobic pocket is required for binding. CIB1 is largely monomeric in the calcium-bound state, distinguishing it from NCS proteins.","method":"X-ray crystallography, circular dichroism, mutational analysis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 — crystal structure at 2.0 Å with mutagenesis validation in single rigorous paper","pmids":["15574431"],"is_preprint":false},{"year":2011,"finding":"Solution NMR structures of Ca2+-CIB1 and Mg2+-CIB1 determined; the C-domain EF-hands are smaller/more open compared to crystal structures. EF-hand III is directly involved in binding the integrin αIIb cytoplasmic domain, and the C-terminal helix of Ca2+-CIB1 is displaced upon αIIb binding, as confirmed by backbone amide dynamics measurements.","method":"Solution NMR spectroscopy, chemical shift perturbation, nitroxide surface probe, backbone amide dynamics","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 — NMR structure determination with multiple orthogonal NMR methods validating binding interface","pmids":["21388953"],"is_preprint":false},{"year":1999,"finding":"CIB1 (CIB) binds to the alphaIIb cytoplasmic domain of the platelet integrin alphaIIbbeta3 in a Ca2+-dependent manner with 1:1 stoichiometry and Kd ~700 nM, as measured by isothermal titration calorimetry. In aggregated platelets, CIB and alphaIIbbeta3 co-translocate to the Triton X-100-insoluble cytoskeleton.","method":"Isothermal titration calorimetry, subcellular fractionation, yeast two-hybrid","journal":"The Biochemical journal","confidence":"High","confidence_rationale":"Tier 1–2 — in vitro calorimetry with functional localization experiment, replicated by multiple subsequent studies","pmids":["10477286"],"is_preprint":false},{"year":2002,"finding":"CIB1 binds to the alphaIIb cytoplasmic tail via a membrane-proximal 15-amino acid hydrophobic region (analogous to alpha-helical targets of calcineurin B/calmodulin). Alanine substitutions in the C-terminal hydrophobic pocket of CIB1 abolished alphaIIb binding in 11/12 cases while retaining secondary structure, identifying the C-terminal EF-hand region as the essential integrin-binding site.","method":"Intrinsic tryptophan fluorescence binding assay, circular dichroism, site-directed mutagenesis","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 — in vitro binding assay with systematic mutagenesis, multiple mutants tested","pmids":["12023286"],"is_preprint":false},{"year":2006,"finding":"CIB1 is an endogenous inhibitor of agonist-induced alphaIIbbeta3 integrin activation in platelets/megakaryocytes. Overexpression of CIB1 blocks agonist-induced alphaIIbbeta3 activation, while RNAi-mediated reduction of CIB1 enhances activation. CIB1 inhibits integrin activation by competing with talin for binding to alphaIIbbeta3.","method":"Overexpression and RNAi knockdown in megakaryocytes, integrin activation assays, competition binding","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 — reciprocal gain/loss-of-function with mechanistic competition model, multiple approaches","pmids":["16418530"],"is_preprint":false},{"year":2003,"finding":"CIB1 directly interacts with and co-immunoprecipitates with the platelet integrin GPIIb/IIIa (alphaIIbbeta3) during outside-in signaling upon adhesion to fibrinogen. CIB1 localizes to filopodia and then the membrane periphery of spread platelets. Inhibition of the CIB-GPIIb interaction (by anti-CIB antibody or GPIIb cytoplasmic peptide) blocks lamellipodia but not filopodia formation; adding recombinant CIB rescues spreading, demonstrating that the CIB-GPIIb/IIIa complex is required for outside-in signaling leading to platelet spreading.","method":"Immunoprecipitation, immunofluorescence, intracellular antibody/peptide introduction, rescue with recombinant protein","journal":"Blood","confidence":"High","confidence_rationale":"Tier 2 — co-IP plus functional rescue with recombinant protein, multiple orthogonal approaches","pmids":["12714504"],"is_preprint":false},{"year":2005,"finding":"CIB1 directly and specifically interacts with PAK1, resulting in PAK1 activation both in vitro and in vivo. CIB1 binds PAK1 within discrete regions surrounding the inhibitory switch domain in a calcium-dependent manner. CIB1 overexpression decreases cell migration on fibronectin via a PAK1- and LIM kinase-dependent increase in cofilin phosphorylation. RNAi depletion of CIB1 increases cell migration and reduces adhesion-induced PAK1 activation and cofilin phosphorylation.","method":"In vitro binding assay, co-immunoprecipitation, overexpression and RNAi, cell migration assays, kinase assays, phospho-cofilin western blot","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 — reciprocal gain/loss-of-function with mechanistic pathway placement; in vitro activation assay plus cellular phenotype","pmids":["16061695"],"is_preprint":false},{"year":2009,"finding":"CIB1 binds to apoptosis signal-regulating kinase 1 (ASK1), interferes with TRAF2 recruitment to ASK1, and inhibits ASK1 autophosphorylation on Thr-838, thereby blocking ASK1 activation and downstream stress-activated MAPK signaling. Ca2+ influx reverses CIB1's inhibitory effect on ASK1 activation and cell death in dopaminergic neurons.","method":"Co-immunoprecipitation, in vitro binding, kinase autophosphorylation assay, RNAi, cell death assays","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods including in vitro kinase assay, co-IP, and functional cell death readout","pmids":["19805025"],"is_preprint":false},{"year":2010,"finding":"CIB1 localizes primarily to the sarcolemma in cardiomyocytes, where it anchors calcineurin to the membrane and controls its activation in coordination with the L-type Ca2+ channel. CIB1 was identified as a binding partner of calcineurin B by yeast two-hybrid. Loss of CIB1 in Cib1-/- mice markedly reduces myocardial hypertrophy, fibrosis, and calcineurin-NFAT signaling after pressure overload, while cardiac-specific CIB1 overexpression enhances hypertrophy. Mice lacking calcineurin A beta show no enhancement of hypertrophy with CIB1 overexpression, placing CIB1 upstream of calcineurin in this pathway.","method":"Yeast two-hybrid, subcellular fractionation/immunofluorescence localization, Cib1-/- mouse phenotyping, cardiac-specific transgenic overexpression, epistasis with calcineurin A beta knockout","journal":"Nature medicine","confidence":"High","confidence_rationale":"Tier 2 — genetic epistasis in vivo plus localization with functional consequence; multiple orthogonal approaches in single study","pmids":["20639889"],"is_preprint":false},{"year":2003,"finding":"CIB1 (CIB) co-immunoprecipitates with the polo-like kinase Snk and inhibits Snk kinase activity, functioning as a negative regulator of Snk kinase activity.","method":"Co-immunoprecipitation, in vitro kinase assay","journal":"Molecular cancer research","confidence":"Medium","confidence_rationale":"Tier 2 — co-IP plus in vitro kinase inhibition assay in single paper","pmids":["12651910"],"is_preprint":false},{"year":2011,"finding":"CIB1 constitutively interacts with polo-like kinase 3 (PLK3) independent of intracellular Ca2+, and this interaction inhibits PLK3 kinase activity in a Ca2+-dependent manner, both in vitro and in vivo.","method":"Co-immunoprecipitation, in vitro binding assay, in vitro and in vivo kinase activity assays","journal":"International journal of cancer","confidence":"Medium","confidence_rationale":"Tier 2 — in vitro kinase inhibition assay plus cellular kinase assay, single lab","pmids":["20473878"],"is_preprint":false},{"year":2001,"finding":"CIB1 interacts exclusively with activated (V12) Rac3 (not Rac1 or Rac2), mediated by the C-terminal end of Rac3 and membrane localization. Co-expression of V12Rac3 and CIB1 stimulates alphaIIbbeta3-mediated adhesion and spreading on fibrinogen. Adhesion through alphaIIbbeta3 specifically increases GTP-bound Rac3 but not Rac1.","method":"Yeast two-hybrid, co-immunoprecipitation, immunofluorescence colocalization, Triton-insoluble fractionation, GTPase pull-down, adhesion and spreading assays","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2–3 — multiple methods showing specificity of CIB1-Rac3 interaction and functional consequence, single lab","pmids":["11756406"],"is_preprint":false},{"year":2006,"finding":"CIB1 binds to all mammalian InsP3 receptor isoforms in a Ca2+-sensitive manner dependent on its two functional EF-hands, and activates InsP3R channel gating in the absence of InsP3. Pre-exposure to CIB1 in vitro reduces the number of InsP3R channels available for subsequent InsP3 stimulation, and CIB1 overexpression attenuates InsP3R-dependent Ca2+ signaling.","method":"Co-immunoprecipitation, single-channel patch clamp, in vitro channel gating assay, Ca2+ imaging with overexpression/knockdown","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1–2 — single-channel electrophysiology plus mutagenesis of EF-hands plus functional Ca2+ signaling assays","pmids":["16723353"],"is_preprint":false},{"year":2008,"finding":"CIB1 acts as a general inhibitor of InsP3-dependent Ca2+ release in vivo. Depletion of CIB1 by shRNA increased Ca2+ responses to InsP3-generating ligands (ATP, UTP, carbachol); overexpression of CIB1 reduced Ca2+ responses. This effect was dependent on the thapsigargin-sensitive ER Ca2+ store and independent of extracellular Ca2+, consistent with CIB1 acting on the InsP3 receptor.","method":"shRNA knockdown, overexpression, FURA-2 Ca2+ imaging, pharmacological dissection","journal":"Journal of neurochemistry","confidence":"Medium","confidence_rationale":"Tier 2–3 — reciprocal gain/loss-of-function with defined pathway placement, single lab","pmids":["18627437"],"is_preprint":false},{"year":2006,"finding":"CIB1 is essential for spermatogenesis: Cib1-/- male mice are sterile due to disruption of the haploid phase of spermatogenesis, associated with increased germ cell apoptosis and loss of elongated spermatids/sperm. Cib1-/- mouse embryonic fibroblasts show markedly slower growth. Cib1-/- testes show increased Cdc2/Cdk1 mRNA and protein expression.","method":"Homologous recombination knockout, histology, TUNEL apoptosis assay, RT-PCR, western blot, MEF growth assay","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 — germline knockout with defined cellular and molecular phenotypes","pmids":["16982698"],"is_preprint":false},{"year":2007,"finding":"CIB1 deficiency in Cib1-/- mice results in impaired thrombosis: increased tail bleeding time, rebleeding, delayed carotid artery occlusion, and unstable thrombus formation. Cib1-/- platelets show reduced spreading on fibrinogen and reduced outside-in signaling-dependent beta3 tyrosine phosphorylation, while inside-out signaling (agonist-induced aggregation and fibrinogen binding) is unaffected.","method":"Cib1-/- knockout mice, tail bleeding assay, intravital microscopy, platelet spreading assay, western blot for beta3 phosphorylation, aggregation assays","journal":"Journal of thrombosis and haemostasis","confidence":"High","confidence_rationale":"Tier 2 — in vivo and ex vivo assays with genetic model clearly distinguishing inside-out from outside-in signaling","pmids":["19691476"],"is_preprint":false},{"year":2007,"finding":"CIB1 regulates endothelial cell migration, proliferation, and tube formation. Loss of CIB1 decreases PAK1 activation, downstream ERK1/2 activation, and MMP-2 expression in endothelial cells. Cib1-/- mice show reduced growth factor-induced microvessel sprouting and impaired ischemia-induced retinal and hindlimb angiogenesis.","method":"shRNA knockdown and Cib1-/- knockout, endothelial cell migration/proliferation/tubule assays, kinase activity assays, ex vivo organ culture, in vivo Matrigel plug and hindlimb ischemia model","journal":"Circulation research","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal in vitro and in vivo assays with pathway placement through PAK1-ERK1/2-MMP2","pmids":["17975111"],"is_preprint":false},{"year":2012,"finding":"CIB1 depletion in cancer cells promotes non-apoptotic, caspase-independent cell death requiring nuclear GAPDH accumulation. CIB1 supports PI3K/AKT and Ras/MEK/ERK signaling; its depletion disrupts both pathways synergistically. AKT inhibition alone maximally induces GAPDH nuclear accumulation, while concurrent ERK inhibition plus GAPDH nuclear accumulation is required for a DNA damage response and subsequent cell death.","method":"RNAi depletion, pharmacological PI3K/AKT and MEK/ERK inhibition, subcellular fractionation for GAPDH, flow cytometry, immunoblotting","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 — multiple pathway dissection methods, single lab","pmids":["22964641"],"is_preprint":false},{"year":2016,"finding":"CIB1 facilitates agonist-induced plasma membrane localization of sphingosine kinase 1 (SK1) via its Ca2+-myristoyl switch function. CIB1 overexpression drives SK1 to the plasma membrane, enhancing membrane-associated SK1 enzymatic activity and oncogenic signaling. CIB1 overexpression alone is sufficient to induce neoplastic transformation in a SK1-dependent manner, and CIB1 knockdown inhibits neoplastic growth induced by oncogenic Ras.","method":"Overexpression and shRNA knockdown, subcellular fractionation, SK1 activity assay, transformation assays, epistasis with SK1","journal":"Oncogene","confidence":"Medium","confidence_rationale":"Tier 2 — functional transformation assay with mechanistic subcellular localization data and SK1 epistasis, single lab","pmids":["27941888"],"is_preprint":false},{"year":2017,"finding":"CIB1 interacts with the catalytic domain of type III CD38 (cytosol-facing orientation) both in vivo and in vitro, as confirmed by co-immunoprecipitation, ELISA, and bimolecular fluorescence complementation. The N-terminus of CIB1 is the interacting domain. shRNA knockdown and CRISPR/Cas9 knockout of CIB1 directly reduces cellular cADPR levels, demonstrating that CIB1 modulates type III CD38-mediated cADPR synthesis.","method":"Yeast two-hybrid, co-immunoprecipitation, ELISA, bimolecular fluorescence complementation, shRNA knockdown, CRISPR/Cas9 knockout, cADPR measurement","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal interaction methods plus genetic knockout with direct biochemical readout","pmids":["28720704"],"is_preprint":false},{"year":2018,"finding":"CIB1 forms a protein complex with EVER1 (TMC6) and EVER2 (TMC8) in keratinocytes. CIB1 protein expression is lost in EVER1- or EVER2-deficient cells. CIB1 interacts with HPV E5 (alpha-HPV16) and E8 (gamma-HPV4) proteins in keratinocytes, suggesting CIB1 acts as a restriction factor against HPVs. Loss-of-function CIB1 mutations cause epidermodysplasia verruciformis with selective susceptibility to beta-HPVs.","method":"Co-immunoprecipitation, patient genetic analysis (null mutations), keratinocyte expression studies, loss-of-function cellular phenotyping","journal":"The Journal of experimental medicine","confidence":"High","confidence_rationale":"Tier 2 — human genetic model with multiple biochemical interaction assays; replicated across patient samples","pmids":["30068544"],"is_preprint":false},{"year":2020,"finding":"CHIP (carboxyl-terminus of Hsp70-interacting protein), a ubiquitin E3 ligase, promotes polyubiquitination and proteasomal degradation of CIB1. Lysine residues 10 and 65 of CIB1 are the ubiquitination sites. CHIP-mediated CIB1 downregulation suppresses epithelial-mesenchymal transition and metastasis of lung adenocarcinoma cells.","method":"Mass spectrometry (interactome), co-immunoprecipitation, ubiquitination assay, site-directed mutagenesis of ubiquitin acceptor sites, in vitro and in vivo metastasis assays","journal":"Cell death and differentiation","confidence":"Medium","confidence_rationale":"Tier 2 — MS identification plus mutagenesis of ubiquitination sites plus functional consequence, single lab","pmids":["33082516"],"is_preprint":false},{"year":2013,"finding":"CIB1 interacts with multiple alpha-integrin cytoplasmic tails beyond alphaIIb, all sharing a conserved consensus binding site (I/L-x-x-x-L/M-W/Y-K-x-G-F-F). Binding is driven by hydrophobic interactions with the CIB1 hydrophobic pocket. Novel in vivo CIB1-integrin interactions validated by co-immunoprecipitation; competition binding confirmed that other alpha-integrin CTs displace alphaIIb from CIB1.","method":"Computational docking (replica exchange discrete molecular dynamics), co-immunoprecipitation, solid-phase competitive binding assay, isothermal titration calorimetry","journal":"Biochemistry","confidence":"Medium","confidence_rationale":"Tier 2 — computational prediction validated by multiple in vitro and in vivo binding methods","pmids":["24011356"],"is_preprint":false},{"year":2014,"finding":"CIB1 synergizes with EphrinA2 (EphA2) to coordinate macropinocytic entry of KSHV in endothelial cells. CIB1 is recruited to membrane blebs and Rab5-positive macropinocytic vesicles during infection. CIB1 knockdown reduces EphA2, Src, and ERK1/2 activation induced by KSHV. By mass spectrometry, CIB1 and EphA2 simultaneously associate with myosin IIA and alpha-actinin 4; CIB1 knockdown reduces EphA2's association with these actin cytoskeletal components.","method":"shRNA knockdown, overexpression, single virus particle tracking (DiI/BrdU labeling), co-immunoprecipitation, mass spectrometry, Rab5 colocalization, kinase activation assays","journal":"PLoS pathogens","confidence":"Medium","confidence_rationale":"Tier 2–3 — multiple complementary methods in single study; pathway placement via kinase activation assays and MS","pmids":["24550731"],"is_preprint":false},{"year":2007,"finding":"CIB1 binds to the IQ motifs in the myo1c regulatory domain, competing with calmodulin for binding. CIB1 co-localizes with myo1c in cells (endogenous proteins). CaBP1 has higher apparent affinity for myo1c than CIB1; both proteins better compete with calmodulin in the presence of calcium.","method":"Pull-down assay, fluorescence microscopy colocalization, competitive binding assay","journal":"Journal of muscle research and cell motility","confidence":"Medium","confidence_rationale":"Tier 3 — pull-down plus colocalization, competition assay; single lab, limited mechanistic follow-up","pmids":["17994197"],"is_preprint":false},{"year":1997,"finding":"CIB1 (described as KIP, a novel Ca2+-binding protein with ~26% identity to calcineurin B) was identified as interacting with DNA-PKcs by yeast two-hybrid screening of DNA-PKcs, and the interaction was confirmed biochemically.","method":"Yeast two-hybrid, biochemical confirmation","journal":"Mutation research","confidence":"Low","confidence_rationale":"Tier 3 — single yeast two-hybrid plus biochemical confirmation; functional consequence not fully defined for CIB1","pmids":["9372844"],"is_preprint":false},{"year":2004,"finding":"CIB1 (KIP) was identified as binding to the catalytic subunit of telomerase (hTERT) by yeast two-hybrid. Co-immunoprecipitation showed CIB1-hTERT complexes in cells; immunolocalization demonstrated CIB1 co-localizes with hTERT in the nucleus. Overexpression of CIB1 increases endogenous telomerase activity and leads to telomere lengthening.","method":"Yeast two-hybrid, co-immunoprecipitation, immunofluorescence colocalization, in vitro binding, telomerase activity assay, telomere length analysis","journal":"The Journal of biological chemistry","confidence":"Medium","confidence_rationale":"Tier 2–3 — multiple methods confirming interaction plus functional telomerase and telomere length readout, single lab","pmids":["15190070"],"is_preprint":false},{"year":2002,"finding":"CIB1 interacts with NBR1 in yeast two-hybrid assays. Co-expression of NBR1 and CIB1 shifts CIB1 protein localization from the nucleus to the perinuclear compartment.","method":"Yeast two-hybrid, co-transfection and immunofluorescence","journal":"European journal of biochemistry","confidence":"Low","confidence_rationale":"Tier 3 — yeast two-hybrid plus localization shift with limited mechanistic follow-up","pmids":["11856312"],"is_preprint":false},{"year":2008,"finding":"CIB1, CIB2, and CIB3 all bind specifically to the alphaIIb cytoplasmic tail peptide in vitro. In Cib1-/- megakaryocytes, CIB3 mRNA is upregulated, suggesting functional compensation. Protein modeling shows CIBs 1–3 share a conserved hydrophobic binding pocket.","method":"In vitro binding assay, RT-PCR, homology modeling","journal":"Thrombosis and haemostasis","confidence":"Medium","confidence_rationale":"Tier 3 — in vitro binding with genetic compensation evidence and structural modeling, single lab","pmids":["18989529"],"is_preprint":false},{"year":2015,"finding":"CIB1 depletion causes significant cell death in the majority of TNBC cell lines tested. Elevated AKT activation status and low PTEN expression predict sensitivity to CIB1 depletion. CIB1 knockdown causes dramatic shrinkage of MDA-MB-468 xenograft tumors in vivo, and RNA-seq shows activation of gene programs associated with decreased proliferation and increased cell death.","method":"Inducible RNAi, clonogenic assay, flow cytometry, western blotting, xenograft tumor model, RNA-sequencing","journal":"Breast cancer research and treatment","confidence":"Medium","confidence_rationale":"Tier 2 — in vitro and in vivo loss-of-function with pathway analysis and predictive biomarker identification, single lab","pmids":["26105795"],"is_preprint":false}],"current_model":"CIB1 is a ubiquitously expressed, EF-hand-containing Ca2+-binding protein that lacks intrinsic enzymatic activity but acts as a multifunctional regulatory scaffold: it binds the αIIb integrin cytoplasmic tail (via a C-terminal hydrophobic pocket) to competitively inhibit talin-mediated integrin αIIbbeta3 activation and regulate outside-in signaling and platelet spreading; it directly activates PAK1 in a Ca2+-dependent manner to control cofilin phosphorylation and cell migration; it anchors calcineurin to the sarcolemma via calcineurin B interaction to regulate pathological cardiac hypertrophy; it inhibits ASK1 autophosphorylation to suppress stress-activated MAPK signaling in a Ca2+-sensitive fashion; it modulates InsP3 receptor gating; it facilitates plasma membrane localization of sphingosine kinase 1 to promote oncogenic Ras signaling; it supports PI3K/AKT and MEK/ERK survival signaling in cancer cells; it forms a complex with EVER1/EVER2 in keratinocytes to mediate intrinsic immunity against beta-papillomaviruses; and it is itself subject to proteasomal degradation via CHIP-mediated ubiquitination at Lys10 and Lys65."},"narrative":{"teleology":[{"year":1999,"claim":"Establishing CIB1 as a direct, Ca²⁺-dependent binding partner of the αIIb integrin cytoplasmic domain answered whether this novel calcineurin-B-like protein had a specific receptor target in platelets.","evidence":"Isothermal titration calorimetry measuring 1:1 stoichiometry and ~700 nM Kd, plus yeast two-hybrid and co-fractionation with αIIbβ3 in activated platelets","pmids":["10477286"],"confidence":"High","gaps":["Functional consequence of αIIb binding in platelets not yet demonstrated","Whether CIB1 binds other integrin α-subunits unknown"]},{"year":2002,"claim":"Mapping the CIB1-integrin interface to the C-terminal hydrophobic pocket established the structural basis for ligand recognition, showing CIB1 uses a calmodulin/calcineurin-B-like target-binding mode.","evidence":"Systematic alanine scanning mutagenesis of 12 hydrophobic pocket residues with tryptophan fluorescence binding assay and CD confirmation of fold integrity","pmids":["12023286"],"confidence":"High","gaps":["Atomic-resolution structure of the CIB1–αIIb complex not yet determined","Whether the same pocket engages non-integrin partners unknown"]},{"year":2003,"claim":"Demonstrating that CIB1 is required for platelet lamellipodia formation during outside-in signaling resolved whether the CIB1–αIIbβ3 interaction had functional significance beyond binding.","evidence":"Co-IP of endogenous proteins during fibrinogen adhesion; intracellular anti-CIB antibody and peptide inhibition block spreading; recombinant CIB1 rescues the phenotype","pmids":["12714504"],"confidence":"High","gaps":["Downstream signaling intermediates linking CIB1 to cytoskeletal reorganization not defined","In vivo platelet function in CIB1-null animals not yet tested"]},{"year":2004,"claim":"The 2.0 Å crystal structure of Ca²⁺-bound CIB1 revealed four EF-hands with only the C-terminal pair competent for Ca²⁺ binding, a calcineurin-B-like fold, and a monomeric state, providing the first atomic framework for understanding CIB1 partner recognition.","evidence":"X-ray crystallography at 2.0 Å resolution with CD and mutagenesis validation","pmids":["15574431"],"confidence":"High","gaps":["Apo- and Mg²⁺-bound structures not yet available","Structural basis for discrimination among partners unresolved"]},{"year":2005,"claim":"Identification of PAK1 as a direct CIB1-activated kinase established CIB1 as an upstream regulator of the PAK1–LIMK–cofilin axis controlling cell migration, extending its role beyond integrins.","evidence":"In vitro kinase activation assay, co-IP, reciprocal overexpression/RNAi with migration and cofilin phosphorylation readouts","pmids":["16061695"],"confidence":"High","gaps":["Whether CIB1 activates PAK1 in platelets specifically unknown","Structural basis of PAK1 activation by CIB1 not determined"]},{"year":2006,"claim":"Showing that CIB1 competitively inhibits talin binding to αIIb to suppress inside-out integrin activation resolved the paradox of CIB1 promoting outside-in but restraining inside-out signaling, establishing CIB1 as a bidirectional integrin regulator.","evidence":"Overexpression blocks and RNAi enhances agonist-induced αIIbβ3 activation in megakaryocytes; competition binding with talin","pmids":["16418530"],"confidence":"High","gaps":["In vivo consequence in CIB1-null platelets not yet shown at this time","Whether CIB1 regulates other integrin α-subunit activation in non-platelet cells untested"]},{"year":2006,"claim":"CIB1 binding to InsP3 receptors and direct activation of channel gating demonstrated a second Ca²⁺-regulatory function, linking CIB1 to intracellular Ca²⁺ store mobilization.","evidence":"Single-channel patch clamp showing CIB1 opens InsP3R without InsP3; EF-hand mutants lose binding; overexpression attenuates InsP3R-dependent Ca²⁺ signaling","pmids":["16723353"],"confidence":"High","gaps":["Physiological context where CIB1–InsP3R interaction dominates undefined","Whether CIB1 modulates store-operated Ca²⁺ entry indirectly not tested"]},{"year":2006,"claim":"Cib1⁻/⁻ male sterility due to disrupted spermatogenesis revealed an essential developmental role for CIB1 beyond platelets and signaling.","evidence":"Germline knockout with histological loss of elongated spermatids, increased germ cell apoptosis, and elevated Cdk1 expression","pmids":["16982698"],"confidence":"High","gaps":["Molecular mechanism linking CIB1 loss to spermatogenic arrest not defined","Whether PAK1 or integrin pathways mediate this phenotype untested"]},{"year":2007,"claim":"Cib1⁻/⁻ mice confirmed CIB1 is required in vivo for stable thrombus formation and outside-in (but not inside-out) integrin signaling, validating earlier cell-based findings.","evidence":"Extended tail bleeding, unstable thrombi by intravital microscopy, reduced β3 phosphorylation and spreading ex vivo, normal aggregation","pmids":["19691476"],"confidence":"High","gaps":["Compensatory upregulation of CIB3 may mask full phenotype","Mechanism connecting CIB1 to β3 tyrosine phosphorylation not resolved"]},{"year":2007,"claim":"Extension of the CIB1–PAK1 axis to angiogenesis demonstrated that CIB1 regulates endothelial cell migration, proliferation, and in vivo neovascularization through PAK1–ERK1/2–MMP2 signaling.","evidence":"shRNA and Cib1⁻/⁻ mice with impaired ischemia-induced angiogenesis; reduced PAK1 and ERK1/2 activation and MMP-2 expression in endothelial cells","pmids":["17975111"],"confidence":"High","gaps":["Whether CIB1's integrin-regulatory and PAK1-activating roles are separable in endothelial cells unknown","Therapeutic targeting implications not tested"]},{"year":2009,"claim":"CIB1 binding to ASK1 and inhibition of its autophosphorylation, reversed by Ca²⁺ influx, established CIB1 as a Ca²⁺-sensitive brake on stress-activated MAPK signaling and cell death.","evidence":"Co-IP, in vitro kinase assay showing inhibition of Thr-838 autophosphorylation, TRAF2 displacement, Ca²⁺-dependent relief in dopaminergic neurons","pmids":["19805025"],"confidence":"High","gaps":["In vivo relevance in neurodegeneration not tested with Cib1⁻/⁻ mice","Whether CIB1–ASK1 is relevant outside neuronal cells untested"]},{"year":2010,"claim":"CIB1 anchoring calcineurin to the sarcolemma to drive pathological cardiac hypertrophy, demonstrated by genetic epistasis with calcineurin Aβ, placed CIB1 as a critical spatial regulator of calcineurin-NFAT signaling in the heart.","evidence":"Cib1⁻/⁻ mice resist pressure-overload hypertrophy; cardiac CIB1 transgenic enhances hypertrophy unless calcineurin Aβ is deleted; yeast two-hybrid with calcineurin B; sarcolemmal localization by fractionation","pmids":["20639889"],"confidence":"High","gaps":["Whether CIB1 regulates calcineurin in non-cardiac tissues unknown","Structural basis of CIB1–calcineurin B interaction not determined"]},{"year":2011,"claim":"Solution NMR structures revealed that EF-hand III directly contacts the αIIb tail and the C-terminal helix is displaced upon binding, providing the first dynamic picture of the CIB1–integrin interaction.","evidence":"NMR chemical shift perturbation and backbone amide dynamics for Ca²⁺-CIB1 and Mg²⁺-CIB1 ± αIIb peptide","pmids":["21388953"],"confidence":"High","gaps":["Full NMR structure of the CIB1–αIIb complex not determined","How divalent cation state switches partner selectivity not fully explained"]},{"year":2013,"claim":"Extension of CIB1 binding to multiple α-integrin cytoplasmic tails via a conserved consensus motif broadened CIB1 from a platelet-specific to a general integrin regulator.","evidence":"Computational docking validated by co-IP and competitive binding assays for multiple α-integrins","pmids":["24011356"],"confidence":"Medium","gaps":["Functional consequence of CIB1 binding to non-αIIb integrins not established in vivo","Whether CIB1 regulates inside-out activation for all bound integrins untested"]},{"year":2016,"claim":"CIB1's Ca²⁺-myristoyl switch facilitating sphingosine kinase 1 plasma membrane translocation and oncogenic Ras signaling established CIB1 as a lipid signaling scaffold with transforming potential.","evidence":"CIB1 overexpression drives SK1 to plasma membrane and induces transformation in a SK1-dependent manner; CIB1 knockdown suppresses Ras-driven neoplastic growth","pmids":["27941888"],"confidence":"Medium","gaps":["Whether the myristoyl switch is required for all CIB1 membrane-associated functions untested","In vivo tumor model with genetic CIB1 loss not performed"]},{"year":2017,"claim":"CIB1 interaction with type III CD38 and regulation of cADPR synthesis revealed an unexpected role in NAD⁺ metabolite signaling.","evidence":"Multiple interaction methods (Y2H, co-IP, BiFC, ELISA); CRISPR knockout reduces cellular cADPR","pmids":["28720704"],"confidence":"High","gaps":["Physiological consequence of altered cADPR levels upon CIB1 loss not characterized","Whether this pathway intersects CIB1's Ca²⁺ regulatory functions unknown"]},{"year":2018,"claim":"Human loss-of-function CIB1 mutations causing epidermodysplasia verruciformis, and CIB1 forming a complex with EVER1/EVER2, established CIB1 as an essential component of intrinsic anti-HPV immunity in keratinocytes.","evidence":"Patient null mutations; CIB1 protein lost in EVER1/EVER2-deficient cells; co-IP of CIB1–EVER1/EVER2 complex; CIB1 interacts with HPV E5 and E8","pmids":["30068544"],"confidence":"High","gaps":["Mechanism by which CIB1–EVER complex restricts β-HPV replication not defined","Whether CIB1's Ca²⁺-binding activity is required for antiviral function untested"]},{"year":2020,"claim":"CHIP-mediated polyubiquitination of CIB1 at Lys10 and Lys65 targeting it for proteasomal degradation defined the first regulated turnover mechanism for CIB1, with functional consequences for EMT and metastasis.","evidence":"Mass spectrometry interactome, co-IP, ubiquitination assay with K10R/K65R mutants, in vivo metastasis assay","pmids":["33082516"],"confidence":"Medium","gaps":["Signals triggering CHIP-mediated CIB1 degradation not identified","Whether other E3 ligases also regulate CIB1 stability unknown"]},{"year":null,"claim":"How CIB1 discriminates among its diverse binding partners in a context-dependent manner, and whether its Ca²⁺-myristoyl switch is universally required for membrane-associated functions, remain major unresolved questions.","evidence":"","pmids":[],"confidence":"High","gaps":["No co-crystal or cryo-EM structure of CIB1 bound to any full-length partner","Integrated model of how Ca²⁺ concentration switches CIB1 between inhibitory and activating modes lacking","Whether CIB1 family members (CIB2–4) are functionally redundant in vivo not systematically tested"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[4,6,7,9,10,12,18]},{"term_id":"GO:0008289","term_label":"lipid binding","supporting_discovery_ids":[0,1,2]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[8,18,20]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[5,8,18]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[19]},{"term_id":"GO:0005856","term_label":"cytoskeleton","supporting_discovery_ids":[2,5]}],"pathway":[{"term_id":"R-HSA-109582","term_label":"Hemostasis","supporting_discovery_ids":[4,5,15]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[6,7,8,17,18]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[20]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[14,16]}],"complexes":["EVER1/EVER2/CIB1 complex"],"partners":["ITGA2B","PAK1","ASK1","PPP3CB","SPHK1","ITPR1","CD38","STUB1"],"other_free_text":[]},"mechanistic_narrative":"CIB1 is a calcium- and integrin-binding protein that functions as a multifunctional regulatory scaffold, coupling Ca²⁺ sensing to integrin signaling, kinase regulation, ion channel modulation, and innate immunity. Structurally, CIB1 is a compact, predominantly monomeric α-helical protein with four EF-hands (the C-terminal pair binding Ca²⁺) and a conserved hydrophobic pocket that engages the αIIb integrin cytoplasmic tail to competitively inhibit talin-mediated inside-out integrin activation while promoting outside-in signaling required for platelet spreading and stable thrombus formation [PMID:15574431, PMID:16418530, PMID:19691476]. CIB1 directly activates PAK1 in a Ca²⁺-dependent manner to regulate cofilin phosphorylation, cell migration, and angiogenesis; inhibits ASK1 autophosphorylation to suppress stress-activated MAPK signaling; anchors calcineurin to the sarcolemma to drive pathological cardiac hypertrophy; modulates InsP3 receptor gating and Ca²⁺ release; and facilitates sphingosine kinase 1 plasma membrane translocation to support oncogenic Ras signaling [PMID:16061695, PMID:19805025, PMID:20639889, PMID:16723353, PMID:27941888]. Loss-of-function mutations in CIB1 cause epidermodysplasia verruciformis with selective susceptibility to β-papillomaviruses, reflecting its role as a subunit of the EVER1/EVER2 restriction factor complex in keratinocytes [PMID:30068544]."},"prefetch_data":{"uniprot":{"accession":"Q99828","full_name":"Calcium and integrin-binding protein 1","aliases":["Calcium- and integrin-binding protein","CIBP","Calmyrin","DNA-PKcs-interacting protein","Kinase-interacting protein","KIP","SNK-interacting protein 2-28","SIP2-28"],"length_aa":191,"mass_kda":21.7,"function":"Calcium-binding protein that plays a role in the regulation of numerous cellular processes, such as cell differentiation, cell division, cell proliferation, cell migration, thrombosis, angiogenesis, cardiac hypertrophy and apoptosis. Involved in bone marrow megakaryocyte differentiation by negatively regulating thrombopoietin-mediated signaling pathway. Participates in the endomitotic cell cycle of megakaryocyte, a form of mitosis in which both karyokinesis and cytokinesis are interrupted. Plays a role in integrin signaling by negatively regulating alpha-IIb/beta3 activation in thrombin-stimulated megakaryocytes preventing platelet aggregation. Up-regulates PTK2/FAK1 activity, and is also needed for the recruitment of PTK2/FAK1 to focal adhesions; it thus appears to play an important role in focal adhesion formation. Positively regulates cell migration on fibronectin in a CDC42-dependent manner, the effect being negatively regulated by PAK1. Functions as a negative regulator of stress activated MAP kinase (MAPK) signaling pathways. Down-regulates inositol 1,4,5-trisphosphate receptor-dependent calcium signaling. Involved in sphingosine kinase SPHK1 translocation to the plasma membrane in a N-myristoylation-dependent manner preventing TNF-induced apoptosis. Regulates serine/threonine-protein kinase PLK3 activity for proper completion of cell division progression. Plays a role in microtubule (MT) dynamics during neuronal development; disrupts the MT depolymerization activity of STMN2 attenuating NGF-induced neurite outgrowth and the MT reorganization at the edge of lamellipodia. Promotes cardiomyocyte hypertrophy via activation of the calcineurin/NFAT signaling pathway. Stimulates calcineurin PPP3R1 activity by mediating its anchoring to the sarcolemma. In ischemia-induced (pathological or adaptive) angiogenesis, stimulates endothelial cell proliferation, migration and microvessel formation by activating the PAK1 and ERK1/ERK2 signaling pathway. Also promotes cancer cell survival and proliferation. May regulate cell cycle and differentiation of spermatogenic germ cells, and/or differentiation of supporting Sertoli cells. Forms a complex with TMC6/EVER1 and TMC8/EVER2 in lymphocytes and keratynocytes where CIB1 stabilizes TMC6 and TMC8 levels and reciprocally (PubMed:30068544, PubMed:32917726) Acts as a restriction factor that promotes keratinocyte-intrinsic immunity to human beta-papillomaviruses (HPVs) Plays a regulatory role in angiogenesis and tumor growth by mediating PKD/PRKD2-induced vascular endothelial growth factor A (VEGFA) secretion","subcellular_location":"Cytoplasm, perinuclear region; Golgi apparatus, trans-Golgi network","url":"https://www.uniprot.org/uniprotkb/Q99828/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/CIB1","classification":"Not Classified","n_dependent_lines":10,"n_total_lines":1208,"dependency_fraction":0.008278145695364239},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/CIB1","total_profiled":1310},"omim":[{"mim_id":"618267","title":"EPIDERMODYSPLASIA VERRUCIFORMIS, SUSCEPTIBILITY TO, 3; EV3","url":"https://www.omim.org/entry/618267"},{"mim_id":"610646","title":"CALCIUM- AND INTEGRIN-BINDING PROTEIN 4; CIB4","url":"https://www.omim.org/entry/610646"},{"mim_id":"610645","title":"CALCIUM- AND INTEGRIN-BINDING PROTEIN 3; CIB3","url":"https://www.omim.org/entry/610645"},{"mim_id":"605829","title":"TRANSMEMBRANE CHANNEL-LIKE PROTEIN 8; TMC8","url":"https://www.omim.org/entry/605829"},{"mim_id":"605828","title":"TRANSMEMBRANE CHANNEL-LIKE PROTEIN 6; TMC6","url":"https://www.omim.org/entry/605828"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Nucleoplasm","reliability":"Supported"},{"location":"Plasma membrane","reliability":"Supported"},{"location":"Nuclear bodies","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/CIB1"},"hgnc":{"alias_symbol":["SIP2-28","CIB","KIP"],"prev_symbol":[]},"alphafold":{"accession":"Q99828","domains":[{"cath_id":"1.10.238.10","chopping":"10-97","consensus_level":"high","plddt":79.3522,"start":10,"end":97},{"cath_id":"1.10.238.10","chopping":"104-186","consensus_level":"high","plddt":76.6295,"start":104,"end":186}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q99828","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q99828-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q99828-F1-predicted_aligned_error_v6.png","plddt_mean":75.75},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=CIB1","jax_strain_url":"https://www.jax.org/strain/search?query=CIB1"},"sequence":{"accession":"Q99828","fasta_url":"https://rest.uniprot.org/uniprotkb/Q99828.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q99828/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q99828"}},"corpus_meta":[{"pmid":"7649471","id":"PMC_7649471","title":"Kip/Cip and Ink4 Cdk inhibitors cooperate to induce cell cycle arrest in response to TGF-beta.","date":"1995","source":"Genes & development","url":"https://pubmed.ncbi.nlm.nih.gov/7649471","citation_count":915,"is_preprint":false},{"pmid":"18988809","id":"PMC_18988809","title":"Photoexcited CRY2 interacts with CIB1 to regulate transcription and floral initiation in Arabidopsis.","date":"2008","source":"Science (New York, N.Y.)","url":"https://pubmed.ncbi.nlm.nih.gov/18988809","citation_count":578,"is_preprint":false},{"pmid":"11032837","id":"PMC_11032837","title":"Molecular identification and characterization of novel human and mouse concentrative Na+-nucleoside cotransporter proteins (hCNT3 and mCNT3) broadly selective for purine and pyrimidine nucleosides (system cib).","date":"2000","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/11032837","citation_count":300,"is_preprint":false},{"pmid":"27065233","id":"PMC_27065233","title":"Optimized second-generation CRY2-CIB dimerizers and photoactivatable Cre recombinase.","date":"2016","source":"Nature chemical biology","url":"https://pubmed.ncbi.nlm.nih.gov/27065233","citation_count":198,"is_preprint":false},{"pmid":"16631585","id":"PMC_16631585","title":"DAF-16/FOXO regulates transcription of cki-1/Cip/Kip and repression of lin-4 during C. elegans L1 arrest.","date":"2006","source":"Current biology : CB","url":"https://pubmed.ncbi.nlm.nih.gov/16631585","citation_count":197,"is_preprint":false},{"pmid":"10048302","id":"PMC_10048302","title":"Cip/Kip cyclin-dependent kinase inhibitors: brakes of the cell cycle engine during development.","date":"1998","source":"BioEssays : news and reviews in molecular, cellular and developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/10048302","citation_count":171,"is_preprint":false},{"pmid":"9927424","id":"PMC_9927424","title":"Degradation of p27(Kip) cdk inhibitor triggered by Kaposi's sarcoma virus cyclin-cdk6 complex.","date":"1999","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/9927424","citation_count":144,"is_preprint":false},{"pmid":"22154077","id":"PMC_22154077","title":"Multiple degradation pathways regulate versatile CIP/KIP CDK inhibitors.","date":"2011","source":"Trends in cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/22154077","citation_count":132,"is_preprint":false},{"pmid":"19934273","id":"PMC_19934273","title":"p57KIP2: \"Kip\"ing the cell under control.","date":"2009","source":"Molecular cancer research : MCR","url":"https://pubmed.ncbi.nlm.nih.gov/19934273","citation_count":128,"is_preprint":false},{"pmid":"11396613","id":"PMC_11396613","title":"Recent molecular advances in studies of the concentrative Na+-dependent nucleoside transporter (CNT) family: identification and characterization of novel human and mouse proteins (hCNT3 and mCNT3) broadly selective for purine and pyrimidine nucleosides (system cib).","date":"2001","source":"Molecular membrane biology","url":"https://pubmed.ncbi.nlm.nih.gov/11396613","citation_count":114,"is_preprint":false},{"pmid":"12386815","id":"PMC_12386815","title":"Muc4/sialomucin complex, the intramembrane ErbB2 ligand, induces specific phosphorylation of ErbB2 and enhances expression of p27(kip), but does not activate mitogen-activated kinase or protein kinaseB/Akt pathways.","date":"2002","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/12386815","citation_count":114,"is_preprint":false},{"pmid":"11684669","id":"PMC_11684669","title":"lin-35 Rb and cki-1 Cip/Kip cooperate in developmental regulation of G1 progression in C. elegans.","date":"2001","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/11684669","citation_count":110,"is_preprint":false},{"pmid":"30068544","id":"PMC_30068544","title":"The human CIB1-EVER1-EVER2 complex governs keratinocyte-intrinsic immunity to β-papillomaviruses.","date":"2018","source":"The Journal of experimental medicine","url":"https://pubmed.ncbi.nlm.nih.gov/30068544","citation_count":109,"is_preprint":false},{"pmid":"10667572","id":"PMC_10667572","title":"Mechanism for inactivation of the KIP family cyclin-dependent kinase inhibitor genes in gastric cancer cells.","date":"2000","source":"Cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/10667572","citation_count":105,"is_preprint":false},{"pmid":"9053838","id":"PMC_9053838","title":"Induction of Cip/Kip and Ink4 cyclin dependent kinase inhibitors by interferon-alpha in hematopoietic cell lines.","date":"1997","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/9053838","citation_count":105,"is_preprint":false},{"pmid":"9920882","id":"PMC_9920882","title":"RhoA stimulates p27(Kip) degradation through its regulation of cyclin E/CDK2 activity.","date":"1999","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/9920882","citation_count":104,"is_preprint":false},{"pmid":"15574431","id":"PMC_15574431","title":"Structural and biochemical characterization of CIB1 delineates a new family of EF-hand-containing proteins.","date":"2004","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/15574431","citation_count":100,"is_preprint":false},{"pmid":"15317781","id":"PMC_15317781","title":"The bzd gene cluster, coding for anaerobic benzoate catabolism, in Azoarcus sp. strain CIB.","date":"2004","source":"Journal of bacteriology","url":"https://pubmed.ncbi.nlm.nih.gov/15317781","citation_count":98,"is_preprint":false},{"pmid":"24272488","id":"PMC_24272488","title":"Blue light-dependent interaction between cryptochrome2 and CIB1 regulates transcription and leaf senescence in soybean.","date":"2013","source":"The Plant cell","url":"https://pubmed.ncbi.nlm.nih.gov/24272488","citation_count":95,"is_preprint":false},{"pmid":"9789031","id":"PMC_9789031","title":"Reduction in levels of the cyclin-dependent kinase inhibitor p27(kip-1) coupled with transforming growth factor beta neutralization induces cell-cycle entry and increases retroviral transduction of primitive human hematopoietic cells.","date":"1998","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/9789031","citation_count":94,"is_preprint":false},{"pmid":"24497510","id":"PMC_24497510","title":"Arabidopsis JAGGED links floral organ patterning to tissue growth by repressing Kip-related cell cycle inhibitors.","date":"2014","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/24497510","citation_count":88,"is_preprint":false},{"pmid":"10595919","id":"PMC_10595919","title":"Expression of p27(kip) and other cell cycle regulators in malignant peripheral nerve sheath tumors and neurofibromas: the emerging role of p27(kip) in malignant transformation of neurofibromas.","date":"1999","source":"The American journal of pathology","url":"https://pubmed.ncbi.nlm.nih.gov/10595919","citation_count":87,"is_preprint":false},{"pmid":"15647527","id":"PMC_15647527","title":"Overexpression of p27 Kip 1, probability of cell cycle exit, and laminar destination of neocortical neurons.","date":"2005","source":"Cerebral cortex (New York, N.Y. : 1991)","url":"https://pubmed.ncbi.nlm.nih.gov/15647527","citation_count":83,"is_preprint":false},{"pmid":"20639889","id":"PMC_20639889","title":"CIB1 is a regulator of pathological cardiac hypertrophy.","date":"2010","source":"Nature medicine","url":"https://pubmed.ncbi.nlm.nih.gov/20639889","citation_count":81,"is_preprint":false},{"pmid":"15564458","id":"PMC_15564458","title":"Induction of Id1 and Id3 by latent membrane protein 1 of Epstein-Barr virus and regulation of p27/Kip and cyclin-dependent kinase 2 in rodent fibroblast transformation.","date":"2004","source":"Journal of virology","url":"https://pubmed.ncbi.nlm.nih.gov/15564458","citation_count":73,"is_preprint":false},{"pmid":"24101505","id":"PMC_24101505","title":"Arabidopsis CRY2 and ZTL mediate blue-light regulation of the transcription factor CIB1 by distinct mechanisms.","date":"2013","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/24101505","citation_count":72,"is_preprint":false},{"pmid":"16061695","id":"PMC_16061695","title":"Essential role of CIB1 in regulating PAK1 activation and cell migration.","date":"2005","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/16061695","citation_count":71,"is_preprint":false},{"pmid":"10506612","id":"PMC_10506612","title":"Clinical relevance of expression of the CIP/KIP cell-cycle inhibitors p21 and p27 in laryngeal cancer.","date":"1999","source":"Journal of clinical oncology : official journal of the American Society of Clinical Oncology","url":"https://pubmed.ncbi.nlm.nih.gov/10506612","citation_count":71,"is_preprint":false},{"pmid":"10972973","id":"PMC_10972973","title":"Growth inhibition in G(1) and altered expression of cyclin D1 and p27(kip-1 )after forced connexin expression in lung and liver carcinoma cells.","date":"2000","source":"Journal of cellular biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/10972973","citation_count":71,"is_preprint":false},{"pmid":"16418530","id":"PMC_16418530","title":"CIB1 is an endogenous inhibitor of agonist-induced integrin alphaIIbbeta3 activation.","date":"2006","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/16418530","citation_count":70,"is_preprint":false},{"pmid":"12651910","id":"PMC_12651910","title":"The serum-inducible protein kinase Snk is a G1 phase polo-like kinase that is inhibited by the calcium- and integrin-binding protein CIB.","date":"2003","source":"Molecular cancer research : MCR","url":"https://pubmed.ncbi.nlm.nih.gov/12651910","citation_count":69,"is_preprint":false},{"pmid":"16988944","id":"PMC_16988944","title":"Downregulation of the KIP family members p27(KIP1) and p57(KIP2) by SKP2 and the role of methylation in p57(KIP2) inactivation in nonsmall cell lung cancer.","date":"2006","source":"International journal of cancer","url":"https://pubmed.ncbi.nlm.nih.gov/16988944","citation_count":68,"is_preprint":false},{"pmid":"19490616","id":"PMC_19490616","title":"Cip/Kip cyclin-dependent protein kinase inhibitors and the road to polyploidy.","date":"2009","source":"Cell division","url":"https://pubmed.ncbi.nlm.nih.gov/19490616","citation_count":67,"is_preprint":false},{"pmid":"10477286","id":"PMC_10477286","title":"Calcium-dependent properties of CIB binding to the integrin alphaIIb cytoplasmic domain and translocation to the platelet cytoskeleton.","date":"1999","source":"The Biochemical journal","url":"https://pubmed.ncbi.nlm.nih.gov/10477286","citation_count":65,"is_preprint":false},{"pmid":"16982698","id":"PMC_16982698","title":"CIB1 is essential for mouse spermatogenesis.","date":"2006","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/16982698","citation_count":64,"is_preprint":false},{"pmid":"12588841","id":"PMC_12588841","title":"The p27cip/kip ortholog dacapo maintains the Drosophila oocyte in prophase of meiosis I.","date":"2003","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/12588841","citation_count":64,"is_preprint":false},{"pmid":"17123502","id":"PMC_17123502","title":"A cell-autonomous requirement for Cip/Kip cyclin-kinase inhibitors in regulating neuronal cell cycle exit but not differentiation in the developing spinal cord.","date":"2006","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/17123502","citation_count":61,"is_preprint":false},{"pmid":"12714504","id":"PMC_12714504","title":"Association of CIB with GPIIb/IIIa during outside-in signaling is required for platelet spreading on fibrinogen.","date":"2003","source":"Blood","url":"https://pubmed.ncbi.nlm.nih.gov/12714504","citation_count":60,"is_preprint":false},{"pmid":"9372844","id":"PMC_9372844","title":"Interaction between DNA-dependent protein kinase and a novel protein, KIP.","date":"1997","source":"Mutation research","url":"https://pubmed.ncbi.nlm.nih.gov/9372844","citation_count":60,"is_preprint":false},{"pmid":"15634675","id":"PMC_15634675","title":"BzdR, a repressor that controls the anaerobic catabolism of benzoate in Azoarcus sp. CIB, is the first member of a new subfamily of transcriptional regulators.","date":"2005","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/15634675","citation_count":59,"is_preprint":false},{"pmid":"11756406","id":"PMC_11756406","title":"The small GTPase Rac3 interacts with the integrin-binding protein CIB and promotes integrin alpha(IIb)beta(3)-mediated adhesion and spreading.","date":"2001","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/11756406","citation_count":58,"is_preprint":false},{"pmid":"27118676","id":"PMC_27118676","title":"CIB1: a small protein with big ambitions.","date":"2016","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/27118676","citation_count":57,"is_preprint":false},{"pmid":"12023286","id":"PMC_12023286","title":"Molecular basis of CIB binding to the integrin alpha IIb cytoplasmic domain.","date":"2002","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/12023286","citation_count":55,"is_preprint":false},{"pmid":"30126927","id":"PMC_30126927","title":"CIB1 and CO interact to mediate CRY2-dependent regulation of flowering.","date":"2018","source":"EMBO reports","url":"https://pubmed.ncbi.nlm.nih.gov/30126927","citation_count":55,"is_preprint":false},{"pmid":"28720704","id":"PMC_28720704","title":"Cytosolic interaction of type III human CD38 with CIB1 modulates cellular cyclic ADP-ribose levels.","date":"2017","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/28720704","citation_count":53,"is_preprint":false},{"pmid":"12781329","id":"PMC_12781329","title":"Induction of G1 phase arrest in MCF human breast cancer cells by pentagalloylglucose through the down-regulation of CDK4 and CDK2 activities and up-regulation of the CDK inhibitors p27(Kip) and p21(Cip).","date":"2003","source":"Biochemical pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/12781329","citation_count":53,"is_preprint":false},{"pmid":"16723353","id":"PMC_16723353","title":"CIB1, a ubiquitously expressed Ca2+-binding protein ligand of the InsP3 receptor Ca2+ release channel.","date":"2006","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/16723353","citation_count":51,"is_preprint":false},{"pmid":"11679961","id":"PMC_11679961","title":"Hepatitis B virus X protein increases expression of p21(Cip-1/WAF1/MDA6) and p27(Kip-1) in primary mouse hepatocytes, leading to reduced cell cycle progression.","date":"2001","source":"Hepatology (Baltimore, Md.)","url":"https://pubmed.ncbi.nlm.nih.gov/11679961","citation_count":50,"is_preprint":false},{"pmid":"26773810","id":"PMC_26773810","title":"The Arabidopsis glutamate receptor-like gene GLR3.6 controls root development by repressing the Kip-related protein gene KRP4.","date":"2016","source":"Journal of experimental botany","url":"https://pubmed.ncbi.nlm.nih.gov/26773810","citation_count":50,"is_preprint":false},{"pmid":"19805025","id":"PMC_19805025","title":"CIB1 functions as a Ca(2+)-sensitive modulator of stress-induced signaling by targeting ASK1.","date":"2009","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/19805025","citation_count":49,"is_preprint":false},{"pmid":"11886339","id":"PMC_11886339","title":"Underexpression of p27/Kip in thyroid papillary microcarcinomas with gross metastatic disease.","date":"2002","source":"Archives of otolaryngology--head & neck surgery","url":"https://pubmed.ncbi.nlm.nih.gov/11886339","citation_count":48,"is_preprint":false},{"pmid":"15037450","id":"PMC_15037450","title":"Analysis of the spatial expression pattern of seven Kip related proteins (KRPs) in the shoot apex of Arabidopsis thaliana.","date":"2004","source":"Annals of botany","url":"https://pubmed.ncbi.nlm.nih.gov/15037450","citation_count":45,"is_preprint":false},{"pmid":"26259823","id":"PMC_26259823","title":"Whole-genome analysis of Azoarcus sp. strain CIB provides genetic insights to its different lifestyles and predicts novel metabolic features.","date":"2015","source":"Systematic and applied microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/26259823","citation_count":44,"is_preprint":false},{"pmid":"11856312","id":"PMC_11856312","title":"NBR1 interacts with fasciculation and elongation protein zeta-1 (FEZ1) and calcium and integrin binding protein (CIB) and shows developmentally restricted expression in the neural tube.","date":"2002","source":"European journal of biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/11856312","citation_count":43,"is_preprint":false},{"pmid":"23426196","id":"PMC_23426196","title":"Multiple functions of Kip-related protein5 connect endoreduplication and cell elongation.","date":"2013","source":"Plant physiology","url":"https://pubmed.ncbi.nlm.nih.gov/23426196","citation_count":41,"is_preprint":false},{"pmid":"2351058","id":"PMC_2351058","title":"Early determination in the C. elegans embryo: a gene, cib-1, required to specify a set of stem-cell-like blastomeres.","date":"1990","source":"Development (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/2351058","citation_count":41,"is_preprint":false},{"pmid":"15190070","id":"PMC_15190070","title":"DNA-protein kinase catalytic subunit-interacting protein KIP binds telomerase by interacting with human telomerase reverse transcriptase.","date":"2004","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/15190070","citation_count":41,"is_preprint":false},{"pmid":"15936816","id":"PMC_15936816","title":"Absence of p21(CIP 1), p27(KIP 1) and p 57(KIP 2) methylation in MDS and AML.","date":"2005","source":"Leukemia research","url":"https://pubmed.ncbi.nlm.nih.gov/15936816","citation_count":39,"is_preprint":false},{"pmid":"11802199","id":"PMC_11802199","title":"Molecular staging of colorectal cancer in African-American and Caucasian patients using phenotypic expression of p53, Bcl-2, MUC-1 AND p27(kip-1).","date":"2002","source":"International journal of cancer","url":"https://pubmed.ncbi.nlm.nih.gov/11802199","citation_count":38,"is_preprint":false},{"pmid":"22964641","id":"PMC_22964641","title":"CIB1 prevents nuclear GAPDH accumulation and non-apoptotic tumor cell death via AKT and ERK signaling.","date":"2012","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/22964641","citation_count":38,"is_preprint":false},{"pmid":"12133571","id":"PMC_12133571","title":"Inverse relationship between p27/Kip.1 and the F-box protein Skp2 in human astrocytic gliomas by immunohistochemistry and Western blot.","date":"2002","source":"Neuroscience letters","url":"https://pubmed.ncbi.nlm.nih.gov/12133571","citation_count":38,"is_preprint":false},{"pmid":"19691476","id":"PMC_19691476","title":"CIB1 deficiency results in impaired thrombosis: the potential role of CIB1 in outside-in signaling through integrin alpha IIb beta 3.","date":"2009","source":"Journal of thrombosis and haemostasis : JTH","url":"https://pubmed.ncbi.nlm.nih.gov/19691476","citation_count":35,"is_preprint":false},{"pmid":"16790529","id":"PMC_16790529","title":"Connective tissue growth factor/CCN2 stimulates actin disassembly through Akt/protein kinase B-mediated phosphorylation and cytoplasmic translocation of p27(Kip-1).","date":"2006","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/16790529","citation_count":35,"is_preprint":false},{"pmid":"23574394","id":"PMC_23574394","title":"Ectopic expression of Kip-related proteins restrains root-knot nematode-feeding site expansion.","date":"2013","source":"The New phytologist","url":"https://pubmed.ncbi.nlm.nih.gov/23574394","citation_count":34,"is_preprint":false},{"pmid":"16299389","id":"PMC_16299389","title":"The maize aberrant pollen transmission 1 gene is a SABRE/KIP homolog required for pollen tube growth.","date":"2005","source":"Genetics","url":"https://pubmed.ncbi.nlm.nih.gov/16299389","citation_count":34,"is_preprint":false},{"pmid":"17975111","id":"PMC_17975111","title":"CIB1 regulates endothelial cells and ischemia-induced pathological and adaptive angiogenesis.","date":"2007","source":"Circulation research","url":"https://pubmed.ncbi.nlm.nih.gov/17975111","citation_count":33,"is_preprint":false},{"pmid":"24550731","id":"PMC_24550731","title":"CIB1 synergizes with EphrinA2 to regulate Kaposi's sarcoma-associated herpesvirus macropinocytic entry in human microvascular dermal endothelial cells.","date":"2014","source":"PLoS pathogens","url":"https://pubmed.ncbi.nlm.nih.gov/24550731","citation_count":32,"is_preprint":false},{"pmid":"25566967","id":"PMC_25566967","title":"Fenofibrate induces G0/G1 phase arrest by modulating the PPARα/FoxO1/p27 kip pathway in human glioblastoma cells.","date":"2015","source":"Tumour biology : the journal of the International Society for Oncodevelopmental Biology and Medicine","url":"https://pubmed.ncbi.nlm.nih.gov/25566967","citation_count":31,"is_preprint":false},{"pmid":"21822213","id":"PMC_21822213","title":"FBF represses the Cip/Kip cell-cycle inhibitor CKI-2 to promote self-renewal of germline stem cells in C. elegans.","date":"2011","source":"The EMBO journal","url":"https://pubmed.ncbi.nlm.nih.gov/21822213","citation_count":30,"is_preprint":false},{"pmid":"24515438","id":"PMC_24515438","title":"Genetic characterization of the role of the Cip/Kip family of proteins as cyclin-dependent kinase inhibitors and assembly factors.","date":"2014","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/24515438","citation_count":30,"is_preprint":false},{"pmid":"31516890","id":"PMC_31516890","title":"Effect of 5-Aza-2'-Deoxycytidine in Comparison to Valproic Acid and Trichostatin A on Histone Deacetylase 1, DNA Methyltransferase 1, and CIP/KIP Family (p21, p27, and p57) Genes Expression, Cell Growth Inhibition, and Apoptosis Induction in Colon Cancer SW480 Cell Line.","date":"2019","source":"Advanced biomedical research","url":"https://pubmed.ncbi.nlm.nih.gov/31516890","citation_count":30,"is_preprint":false},{"pmid":"16315255","id":"PMC_16315255","title":"Epigenetic inactivation of the CIP/KIP cell-cycle control pathway in acute leukemias.","date":"2005","source":"American journal of hematology","url":"https://pubmed.ncbi.nlm.nih.gov/16315255","citation_count":29,"is_preprint":false},{"pmid":"20805359","id":"PMC_20805359","title":"Cortactin modulates RhoA activation and expression of Cip/Kip cyclin-dependent kinase inhibitors to promote cell cycle progression in 11q13-amplified head and neck squamous cell carcinoma cells.","date":"2010","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/20805359","citation_count":28,"is_preprint":false},{"pmid":"27941888","id":"PMC_27941888","title":"CIB1 contributes to oncogenic signalling by Ras via modulating the subcellular localisation of sphingosine kinase 1.","date":"2016","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/27941888","citation_count":27,"is_preprint":false},{"pmid":"26105795","id":"PMC_26105795","title":"CIB1 depletion impairs cell survival and tumor growth in triple-negative breast cancer.","date":"2015","source":"Breast cancer research and treatment","url":"https://pubmed.ncbi.nlm.nih.gov/26105795","citation_count":26,"is_preprint":false},{"pmid":"20473878","id":"PMC_20473878","title":"Calcium-dependent inhibition of polo-like kinase 3 activity by CIB1 in breast cancer cells.","date":"2011","source":"International journal of cancer","url":"https://pubmed.ncbi.nlm.nih.gov/20473878","citation_count":26,"is_preprint":false},{"pmid":"18989529","id":"PMC_18989529","title":"Characterization of calcium- and integrin-binding protein 1 (CIB1) knockout platelets: potential compensation by CIB family members.","date":"2008","source":"Thrombosis and haemostasis","url":"https://pubmed.ncbi.nlm.nih.gov/18989529","citation_count":26,"is_preprint":false},{"pmid":"20826820","id":"PMC_20826820","title":"Biochemical characterization of the transcriptional regulator BzdR from Azoarcus sp. CIB.","date":"2010","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/20826820","citation_count":26,"is_preprint":false},{"pmid":"24011356","id":"PMC_24011356","title":"Identification of novel integrin binding partners for calcium and integrin binding protein 1 (CIB1): structural and thermodynamic basis of CIB1 promiscuity.","date":"2013","source":"Biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/24011356","citation_count":26,"is_preprint":false},{"pmid":"23385498","id":"PMC_23385498","title":"The role of p21Waf1/CIP1 as a Cip/Kip type cell-cycle regulator in oral squamous cell carcinoma (Review).","date":"2013","source":"Medicina oral, patologia oral y cirugia bucal","url":"https://pubmed.ncbi.nlm.nih.gov/23385498","citation_count":25,"is_preprint":false},{"pmid":"16565223","id":"PMC_16565223","title":"Methylation of INK4 and CIP/KIP families of cyclin-dependent kinase inhibitor in chronic lymphocytic leukaemia in Chinese patients.","date":"2006","source":"Journal of clinical pathology","url":"https://pubmed.ncbi.nlm.nih.gov/16565223","citation_count":25,"is_preprint":false},{"pmid":"17994197","id":"PMC_17994197","title":"CIB1 and CaBP1 bind to the myo1c regulatory domain.","date":"2007","source":"Journal of muscle research and cell motility","url":"https://pubmed.ncbi.nlm.nih.gov/17994197","citation_count":25,"is_preprint":false},{"pmid":"23314608","id":"PMC_23314608","title":"Kip-related protein 3 is required for control of endoreduplication in the shoot apical meristem and leaves of Arabidopsis.","date":"2012","source":"Molecules and cells","url":"https://pubmed.ncbi.nlm.nih.gov/23314608","citation_count":24,"is_preprint":false},{"pmid":"25463440","id":"PMC_25463440","title":"The activity and stability of the intrinsically disordered Cip/Kip protein family are regulated by non-receptor tyrosine kinases.","date":"2014","source":"Journal of molecular biology","url":"https://pubmed.ncbi.nlm.nih.gov/25463440","citation_count":22,"is_preprint":false},{"pmid":"34795874","id":"PMC_34795874","title":"Discovery and Development of Cyclic Peptide Inhibitors of CIB1.","date":"2021","source":"ACS medicinal chemistry letters","url":"https://pubmed.ncbi.nlm.nih.gov/34795874","citation_count":21,"is_preprint":false},{"pmid":"18627437","id":"PMC_18627437","title":"Sweet taste receptor interacting protein CIB1 is a general inhibitor of InsP3-dependent Ca2+ release in vivo.","date":"2008","source":"Journal of neurochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/18627437","citation_count":21,"is_preprint":false},{"pmid":"17162129","id":"PMC_17162129","title":"Expression of Bax, p53, and p27/kip in patients with papillary thyroid carcinoma with or without cervical nodal metastasis.","date":"2007","source":"American journal of otolaryngology","url":"https://pubmed.ncbi.nlm.nih.gov/17162129","citation_count":21,"is_preprint":false},{"pmid":"29857567","id":"PMC_29857567","title":"Synthesis, Structure and Biological Activity of CIA and CIB, Two α-Conotoxins from the Predation-Evoked Venom of Conus catus.","date":"2018","source":"Toxins","url":"https://pubmed.ncbi.nlm.nih.gov/29857567","citation_count":20,"is_preprint":false},{"pmid":"29623071","id":"PMC_29623071","title":"Transcriptional Regulation of the Peripheral Pathway for the Anaerobic Catabolism of Toluene and m-Xylene in Azoarcus sp. CIB.","date":"2018","source":"Frontiers in microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/29623071","citation_count":20,"is_preprint":false},{"pmid":"18177371","id":"PMC_18177371","title":"Identification and analysis of a glutaryl-CoA dehydrogenase-encoding gene and its cognate transcriptional regulator from Azoarcus sp. CIB.","date":"2007","source":"Environmental microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/18177371","citation_count":20,"is_preprint":false},{"pmid":"38561743","id":"PMC_38561743","title":"CIP/KIP and INK4 families as hostages of oncogenic signaling.","date":"2024","source":"Cell division","url":"https://pubmed.ncbi.nlm.nih.gov/38561743","citation_count":19,"is_preprint":false},{"pmid":"33082516","id":"PMC_33082516","title":"CHIP-mediated CIB1 ubiquitination regulated epithelial-mesenchymal transition and tumor metastasis in lung adenocarcinoma.","date":"2020","source":"Cell death and differentiation","url":"https://pubmed.ncbi.nlm.nih.gov/33082516","citation_count":19,"is_preprint":false},{"pmid":"26292757","id":"PMC_26292757","title":"An essential role for Ink4 and Cip/Kip cell-cycle inhibitors in preventing replicative stress.","date":"2015","source":"Cell death and differentiation","url":"https://pubmed.ncbi.nlm.nih.gov/26292757","citation_count":19,"is_preprint":false},{"pmid":"23000166","id":"PMC_23000166","title":"Development of mice without Cip/Kip CDK inhibitors.","date":"2012","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/23000166","citation_count":19,"is_preprint":false},{"pmid":"20804551","id":"PMC_20804551","title":"Tumor growth and angiogenesis is impaired in CIB1 knockout mice.","date":"2010","source":"Journal of angiogenesis research","url":"https://pubmed.ncbi.nlm.nih.gov/20804551","citation_count":19,"is_preprint":false},{"pmid":"14672934","id":"PMC_14672934","title":"The crystal structure of CCG1/TAF(II)250-interacting factor B (CIB).","date":"2003","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/14672934","citation_count":19,"is_preprint":false},{"pmid":"15936818","id":"PMC_15936818","title":"Increase in Ara-C cytotoxicity in the presence of valproate, a histone deacetylase inhibitor, is associated with the concurrent expression of cyclin D1 and p27(Kip 1) in acute myeloblastic leukemia cells.","date":"2005","source":"Leukemia research","url":"https://pubmed.ncbi.nlm.nih.gov/15936818","citation_count":19,"is_preprint":false},{"pmid":"21388953","id":"PMC_21388953","title":"Solution structures of Ca2+-CIB1 and Mg2+-CIB1 and their interactions with the platelet integrin alphaIIb cytoplasmic domain.","date":"2011","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/21388953","citation_count":19,"is_preprint":false},{"pmid":"32971998","id":"PMC_32971998","title":"Enhancing the Rice Seedlings Growth Promotion Abilities of Azoarcus sp. CIB by Heterologous Expression of ACC Deaminase to Improve Performance of Plants Exposed to Cadmium Stress.","date":"2020","source":"Microorganisms","url":"https://pubmed.ncbi.nlm.nih.gov/32971998","citation_count":19,"is_preprint":false},{"pmid":"29017172","id":"PMC_29017172","title":"The Emerging Roles of CIB1 in Cancer.","date":"2017","source":"Cellular physiology and biochemistry : international journal of experimental cellular physiology, biochemistry, and pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/29017172","citation_count":18,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":49633,"output_tokens":7830,"usd":0.133175},"stage2":{"model":"claude-opus-4-6","input_tokens":11535,"output_tokens":4563,"usd":0.257625},"total_usd":0.3908,"stage1_batch_id":"msgbatch_011kfMfE81o6CTcyhVUqumuW","stage2_batch_id":"msgbatch_01DTputS6WNkH745x1nVSoBo","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2004,\n      \"finding\": \"Crystal structure of Ca2+-bound CIB1 determined at 2.0 Å resolution, revealing a compact alpha-helical protein with four EF-hands (last two bind calcium), structural similarity to calcineurin B and neuronal calcium sensor (NCS) proteins, and a conserved hydrophobic pocket implicated in ligand binding; mutagenesis confirmed the hydrophobic pocket is required for binding. CIB1 is largely monomeric in the calcium-bound state, distinguishing it from NCS proteins.\",\n      \"method\": \"X-ray crystallography, circular dichroism, mutational analysis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — crystal structure at 2.0 Å with mutagenesis validation in single rigorous paper\",\n      \"pmids\": [\"15574431\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Solution NMR structures of Ca2+-CIB1 and Mg2+-CIB1 determined; the C-domain EF-hands are smaller/more open compared to crystal structures. EF-hand III is directly involved in binding the integrin αIIb cytoplasmic domain, and the C-terminal helix of Ca2+-CIB1 is displaced upon αIIb binding, as confirmed by backbone amide dynamics measurements.\",\n      \"method\": \"Solution NMR spectroscopy, chemical shift perturbation, nitroxide surface probe, backbone amide dynamics\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — NMR structure determination with multiple orthogonal NMR methods validating binding interface\",\n      \"pmids\": [\"21388953\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1999,\n      \"finding\": \"CIB1 (CIB) binds to the alphaIIb cytoplasmic domain of the platelet integrin alphaIIbbeta3 in a Ca2+-dependent manner with 1:1 stoichiometry and Kd ~700 nM, as measured by isothermal titration calorimetry. In aggregated platelets, CIB and alphaIIbbeta3 co-translocate to the Triton X-100-insoluble cytoskeleton.\",\n      \"method\": \"Isothermal titration calorimetry, subcellular fractionation, yeast two-hybrid\",\n      \"journal\": \"The Biochemical journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — in vitro calorimetry with functional localization experiment, replicated by multiple subsequent studies\",\n      \"pmids\": [\"10477286\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"CIB1 binds to the alphaIIb cytoplasmic tail via a membrane-proximal 15-amino acid hydrophobic region (analogous to alpha-helical targets of calcineurin B/calmodulin). Alanine substitutions in the C-terminal hydrophobic pocket of CIB1 abolished alphaIIb binding in 11/12 cases while retaining secondary structure, identifying the C-terminal EF-hand region as the essential integrin-binding site.\",\n      \"method\": \"Intrinsic tryptophan fluorescence binding assay, circular dichroism, site-directed mutagenesis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — in vitro binding assay with systematic mutagenesis, multiple mutants tested\",\n      \"pmids\": [\"12023286\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"CIB1 is an endogenous inhibitor of agonist-induced alphaIIbbeta3 integrin activation in platelets/megakaryocytes. Overexpression of CIB1 blocks agonist-induced alphaIIbbeta3 activation, while RNAi-mediated reduction of CIB1 enhances activation. CIB1 inhibits integrin activation by competing with talin for binding to alphaIIbbeta3.\",\n      \"method\": \"Overexpression and RNAi knockdown in megakaryocytes, integrin activation assays, competition binding\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal gain/loss-of-function with mechanistic competition model, multiple approaches\",\n      \"pmids\": [\"16418530\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"CIB1 directly interacts with and co-immunoprecipitates with the platelet integrin GPIIb/IIIa (alphaIIbbeta3) during outside-in signaling upon adhesion to fibrinogen. CIB1 localizes to filopodia and then the membrane periphery of spread platelets. Inhibition of the CIB-GPIIb interaction (by anti-CIB antibody or GPIIb cytoplasmic peptide) blocks lamellipodia but not filopodia formation; adding recombinant CIB rescues spreading, demonstrating that the CIB-GPIIb/IIIa complex is required for outside-in signaling leading to platelet spreading.\",\n      \"method\": \"Immunoprecipitation, immunofluorescence, intracellular antibody/peptide introduction, rescue with recombinant protein\",\n      \"journal\": \"Blood\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — co-IP plus functional rescue with recombinant protein, multiple orthogonal approaches\",\n      \"pmids\": [\"12714504\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"CIB1 directly and specifically interacts with PAK1, resulting in PAK1 activation both in vitro and in vivo. CIB1 binds PAK1 within discrete regions surrounding the inhibitory switch domain in a calcium-dependent manner. CIB1 overexpression decreases cell migration on fibronectin via a PAK1- and LIM kinase-dependent increase in cofilin phosphorylation. RNAi depletion of CIB1 increases cell migration and reduces adhesion-induced PAK1 activation and cofilin phosphorylation.\",\n      \"method\": \"In vitro binding assay, co-immunoprecipitation, overexpression and RNAi, cell migration assays, kinase assays, phospho-cofilin western blot\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal gain/loss-of-function with mechanistic pathway placement; in vitro activation assay plus cellular phenotype\",\n      \"pmids\": [\"16061695\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"CIB1 binds to apoptosis signal-regulating kinase 1 (ASK1), interferes with TRAF2 recruitment to ASK1, and inhibits ASK1 autophosphorylation on Thr-838, thereby blocking ASK1 activation and downstream stress-activated MAPK signaling. Ca2+ influx reverses CIB1's inhibitory effect on ASK1 activation and cell death in dopaminergic neurons.\",\n      \"method\": \"Co-immunoprecipitation, in vitro binding, kinase autophosphorylation assay, RNAi, cell death assays\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods including in vitro kinase assay, co-IP, and functional cell death readout\",\n      \"pmids\": [\"19805025\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"CIB1 localizes primarily to the sarcolemma in cardiomyocytes, where it anchors calcineurin to the membrane and controls its activation in coordination with the L-type Ca2+ channel. CIB1 was identified as a binding partner of calcineurin B by yeast two-hybrid. Loss of CIB1 in Cib1-/- mice markedly reduces myocardial hypertrophy, fibrosis, and calcineurin-NFAT signaling after pressure overload, while cardiac-specific CIB1 overexpression enhances hypertrophy. Mice lacking calcineurin A beta show no enhancement of hypertrophy with CIB1 overexpression, placing CIB1 upstream of calcineurin in this pathway.\",\n      \"method\": \"Yeast two-hybrid, subcellular fractionation/immunofluorescence localization, Cib1-/- mouse phenotyping, cardiac-specific transgenic overexpression, epistasis with calcineurin A beta knockout\",\n      \"journal\": \"Nature medicine\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — genetic epistasis in vivo plus localization with functional consequence; multiple orthogonal approaches in single study\",\n      \"pmids\": [\"20639889\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"CIB1 (CIB) co-immunoprecipitates with the polo-like kinase Snk and inhibits Snk kinase activity, functioning as a negative regulator of Snk kinase activity.\",\n      \"method\": \"Co-immunoprecipitation, in vitro kinase assay\",\n      \"journal\": \"Molecular cancer research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — co-IP plus in vitro kinase inhibition assay in single paper\",\n      \"pmids\": [\"12651910\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"CIB1 constitutively interacts with polo-like kinase 3 (PLK3) independent of intracellular Ca2+, and this interaction inhibits PLK3 kinase activity in a Ca2+-dependent manner, both in vitro and in vivo.\",\n      \"method\": \"Co-immunoprecipitation, in vitro binding assay, in vitro and in vivo kinase activity assays\",\n      \"journal\": \"International journal of cancer\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — in vitro kinase inhibition assay plus cellular kinase assay, single lab\",\n      \"pmids\": [\"20473878\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2001,\n      \"finding\": \"CIB1 interacts exclusively with activated (V12) Rac3 (not Rac1 or Rac2), mediated by the C-terminal end of Rac3 and membrane localization. Co-expression of V12Rac3 and CIB1 stimulates alphaIIbbeta3-mediated adhesion and spreading on fibrinogen. Adhesion through alphaIIbbeta3 specifically increases GTP-bound Rac3 but not Rac1.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, immunofluorescence colocalization, Triton-insoluble fractionation, GTPase pull-down, adhesion and spreading assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — multiple methods showing specificity of CIB1-Rac3 interaction and functional consequence, single lab\",\n      \"pmids\": [\"11756406\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"CIB1 binds to all mammalian InsP3 receptor isoforms in a Ca2+-sensitive manner dependent on its two functional EF-hands, and activates InsP3R channel gating in the absence of InsP3. Pre-exposure to CIB1 in vitro reduces the number of InsP3R channels available for subsequent InsP3 stimulation, and CIB1 overexpression attenuates InsP3R-dependent Ca2+ signaling.\",\n      \"method\": \"Co-immunoprecipitation, single-channel patch clamp, in vitro channel gating assay, Ca2+ imaging with overexpression/knockdown\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — single-channel electrophysiology plus mutagenesis of EF-hands plus functional Ca2+ signaling assays\",\n      \"pmids\": [\"16723353\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"CIB1 acts as a general inhibitor of InsP3-dependent Ca2+ release in vivo. Depletion of CIB1 by shRNA increased Ca2+ responses to InsP3-generating ligands (ATP, UTP, carbachol); overexpression of CIB1 reduced Ca2+ responses. This effect was dependent on the thapsigargin-sensitive ER Ca2+ store and independent of extracellular Ca2+, consistent with CIB1 acting on the InsP3 receptor.\",\n      \"method\": \"shRNA knockdown, overexpression, FURA-2 Ca2+ imaging, pharmacological dissection\",\n      \"journal\": \"Journal of neurochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — reciprocal gain/loss-of-function with defined pathway placement, single lab\",\n      \"pmids\": [\"18627437\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2006,\n      \"finding\": \"CIB1 is essential for spermatogenesis: Cib1-/- male mice are sterile due to disruption of the haploid phase of spermatogenesis, associated with increased germ cell apoptosis and loss of elongated spermatids/sperm. Cib1-/- mouse embryonic fibroblasts show markedly slower growth. Cib1-/- testes show increased Cdc2/Cdk1 mRNA and protein expression.\",\n      \"method\": \"Homologous recombination knockout, histology, TUNEL apoptosis assay, RT-PCR, western blot, MEF growth assay\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — germline knockout with defined cellular and molecular phenotypes\",\n      \"pmids\": [\"16982698\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"CIB1 deficiency in Cib1-/- mice results in impaired thrombosis: increased tail bleeding time, rebleeding, delayed carotid artery occlusion, and unstable thrombus formation. Cib1-/- platelets show reduced spreading on fibrinogen and reduced outside-in signaling-dependent beta3 tyrosine phosphorylation, while inside-out signaling (agonist-induced aggregation and fibrinogen binding) is unaffected.\",\n      \"method\": \"Cib1-/- knockout mice, tail bleeding assay, intravital microscopy, platelet spreading assay, western blot for beta3 phosphorylation, aggregation assays\",\n      \"journal\": \"Journal of thrombosis and haemostasis\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — in vivo and ex vivo assays with genetic model clearly distinguishing inside-out from outside-in signaling\",\n      \"pmids\": [\"19691476\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"CIB1 regulates endothelial cell migration, proliferation, and tube formation. Loss of CIB1 decreases PAK1 activation, downstream ERK1/2 activation, and MMP-2 expression in endothelial cells. Cib1-/- mice show reduced growth factor-induced microvessel sprouting and impaired ischemia-induced retinal and hindlimb angiogenesis.\",\n      \"method\": \"shRNA knockdown and Cib1-/- knockout, endothelial cell migration/proliferation/tubule assays, kinase activity assays, ex vivo organ culture, in vivo Matrigel plug and hindlimb ischemia model\",\n      \"journal\": \"Circulation research\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal in vitro and in vivo assays with pathway placement through PAK1-ERK1/2-MMP2\",\n      \"pmids\": [\"17975111\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"CIB1 depletion in cancer cells promotes non-apoptotic, caspase-independent cell death requiring nuclear GAPDH accumulation. CIB1 supports PI3K/AKT and Ras/MEK/ERK signaling; its depletion disrupts both pathways synergistically. AKT inhibition alone maximally induces GAPDH nuclear accumulation, while concurrent ERK inhibition plus GAPDH nuclear accumulation is required for a DNA damage response and subsequent cell death.\",\n      \"method\": \"RNAi depletion, pharmacological PI3K/AKT and MEK/ERK inhibition, subcellular fractionation for GAPDH, flow cytometry, immunoblotting\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — multiple pathway dissection methods, single lab\",\n      \"pmids\": [\"22964641\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"CIB1 facilitates agonist-induced plasma membrane localization of sphingosine kinase 1 (SK1) via its Ca2+-myristoyl switch function. CIB1 overexpression drives SK1 to the plasma membrane, enhancing membrane-associated SK1 enzymatic activity and oncogenic signaling. CIB1 overexpression alone is sufficient to induce neoplastic transformation in a SK1-dependent manner, and CIB1 knockdown inhibits neoplastic growth induced by oncogenic Ras.\",\n      \"method\": \"Overexpression and shRNA knockdown, subcellular fractionation, SK1 activity assay, transformation assays, epistasis with SK1\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — functional transformation assay with mechanistic subcellular localization data and SK1 epistasis, single lab\",\n      \"pmids\": [\"27941888\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"CIB1 interacts with the catalytic domain of type III CD38 (cytosol-facing orientation) both in vivo and in vitro, as confirmed by co-immunoprecipitation, ELISA, and bimolecular fluorescence complementation. The N-terminus of CIB1 is the interacting domain. shRNA knockdown and CRISPR/Cas9 knockout of CIB1 directly reduces cellular cADPR levels, demonstrating that CIB1 modulates type III CD38-mediated cADPR synthesis.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, ELISA, bimolecular fluorescence complementation, shRNA knockdown, CRISPR/Cas9 knockout, cADPR measurement\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal interaction methods plus genetic knockout with direct biochemical readout\",\n      \"pmids\": [\"28720704\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"CIB1 forms a protein complex with EVER1 (TMC6) and EVER2 (TMC8) in keratinocytes. CIB1 protein expression is lost in EVER1- or EVER2-deficient cells. CIB1 interacts with HPV E5 (alpha-HPV16) and E8 (gamma-HPV4) proteins in keratinocytes, suggesting CIB1 acts as a restriction factor against HPVs. Loss-of-function CIB1 mutations cause epidermodysplasia verruciformis with selective susceptibility to beta-HPVs.\",\n      \"method\": \"Co-immunoprecipitation, patient genetic analysis (null mutations), keratinocyte expression studies, loss-of-function cellular phenotyping\",\n      \"journal\": \"The Journal of experimental medicine\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — human genetic model with multiple biochemical interaction assays; replicated across patient samples\",\n      \"pmids\": [\"30068544\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"CHIP (carboxyl-terminus of Hsp70-interacting protein), a ubiquitin E3 ligase, promotes polyubiquitination and proteasomal degradation of CIB1. Lysine residues 10 and 65 of CIB1 are the ubiquitination sites. CHIP-mediated CIB1 downregulation suppresses epithelial-mesenchymal transition and metastasis of lung adenocarcinoma cells.\",\n      \"method\": \"Mass spectrometry (interactome), co-immunoprecipitation, ubiquitination assay, site-directed mutagenesis of ubiquitin acceptor sites, in vitro and in vivo metastasis assays\",\n      \"journal\": \"Cell death and differentiation\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — MS identification plus mutagenesis of ubiquitination sites plus functional consequence, single lab\",\n      \"pmids\": [\"33082516\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"CIB1 interacts with multiple alpha-integrin cytoplasmic tails beyond alphaIIb, all sharing a conserved consensus binding site (I/L-x-x-x-L/M-W/Y-K-x-G-F-F). Binding is driven by hydrophobic interactions with the CIB1 hydrophobic pocket. Novel in vivo CIB1-integrin interactions validated by co-immunoprecipitation; competition binding confirmed that other alpha-integrin CTs displace alphaIIb from CIB1.\",\n      \"method\": \"Computational docking (replica exchange discrete molecular dynamics), co-immunoprecipitation, solid-phase competitive binding assay, isothermal titration calorimetry\",\n      \"journal\": \"Biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — computational prediction validated by multiple in vitro and in vivo binding methods\",\n      \"pmids\": [\"24011356\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"CIB1 synergizes with EphrinA2 (EphA2) to coordinate macropinocytic entry of KSHV in endothelial cells. CIB1 is recruited to membrane blebs and Rab5-positive macropinocytic vesicles during infection. CIB1 knockdown reduces EphA2, Src, and ERK1/2 activation induced by KSHV. By mass spectrometry, CIB1 and EphA2 simultaneously associate with myosin IIA and alpha-actinin 4; CIB1 knockdown reduces EphA2's association with these actin cytoskeletal components.\",\n      \"method\": \"shRNA knockdown, overexpression, single virus particle tracking (DiI/BrdU labeling), co-immunoprecipitation, mass spectrometry, Rab5 colocalization, kinase activation assays\",\n      \"journal\": \"PLoS pathogens\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — multiple complementary methods in single study; pathway placement via kinase activation assays and MS\",\n      \"pmids\": [\"24550731\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2007,\n      \"finding\": \"CIB1 binds to the IQ motifs in the myo1c regulatory domain, competing with calmodulin for binding. CIB1 co-localizes with myo1c in cells (endogenous proteins). CaBP1 has higher apparent affinity for myo1c than CIB1; both proteins better compete with calmodulin in the presence of calcium.\",\n      \"method\": \"Pull-down assay, fluorescence microscopy colocalization, competitive binding assay\",\n      \"journal\": \"Journal of muscle research and cell motility\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 — pull-down plus colocalization, competition assay; single lab, limited mechanistic follow-up\",\n      \"pmids\": [\"17994197\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1997,\n      \"finding\": \"CIB1 (described as KIP, a novel Ca2+-binding protein with ~26% identity to calcineurin B) was identified as interacting with DNA-PKcs by yeast two-hybrid screening of DNA-PKcs, and the interaction was confirmed biochemically.\",\n      \"method\": \"Yeast two-hybrid, biochemical confirmation\",\n      \"journal\": \"Mutation research\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 — single yeast two-hybrid plus biochemical confirmation; functional consequence not fully defined for CIB1\",\n      \"pmids\": [\"9372844\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"CIB1 (KIP) was identified as binding to the catalytic subunit of telomerase (hTERT) by yeast two-hybrid. Co-immunoprecipitation showed CIB1-hTERT complexes in cells; immunolocalization demonstrated CIB1 co-localizes with hTERT in the nucleus. Overexpression of CIB1 increases endogenous telomerase activity and leads to telomere lengthening.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, immunofluorescence colocalization, in vitro binding, telomerase activity assay, telomere length analysis\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — multiple methods confirming interaction plus functional telomerase and telomere length readout, single lab\",\n      \"pmids\": [\"15190070\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2002,\n      \"finding\": \"CIB1 interacts with NBR1 in yeast two-hybrid assays. Co-expression of NBR1 and CIB1 shifts CIB1 protein localization from the nucleus to the perinuclear compartment.\",\n      \"method\": \"Yeast two-hybrid, co-transfection and immunofluorescence\",\n      \"journal\": \"European journal of biochemistry\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 — yeast two-hybrid plus localization shift with limited mechanistic follow-up\",\n      \"pmids\": [\"11856312\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"CIB1, CIB2, and CIB3 all bind specifically to the alphaIIb cytoplasmic tail peptide in vitro. In Cib1-/- megakaryocytes, CIB3 mRNA is upregulated, suggesting functional compensation. Protein modeling shows CIBs 1–3 share a conserved hydrophobic binding pocket.\",\n      \"method\": \"In vitro binding assay, RT-PCR, homology modeling\",\n      \"journal\": \"Thrombosis and haemostasis\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 3 — in vitro binding with genetic compensation evidence and structural modeling, single lab\",\n      \"pmids\": [\"18989529\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"CIB1 depletion causes significant cell death in the majority of TNBC cell lines tested. Elevated AKT activation status and low PTEN expression predict sensitivity to CIB1 depletion. CIB1 knockdown causes dramatic shrinkage of MDA-MB-468 xenograft tumors in vivo, and RNA-seq shows activation of gene programs associated with decreased proliferation and increased cell death.\",\n      \"method\": \"Inducible RNAi, clonogenic assay, flow cytometry, western blotting, xenograft tumor model, RNA-sequencing\",\n      \"journal\": \"Breast cancer research and treatment\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — in vitro and in vivo loss-of-function with pathway analysis and predictive biomarker identification, single lab\",\n      \"pmids\": [\"26105795\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"CIB1 is a ubiquitously expressed, EF-hand-containing Ca2+-binding protein that lacks intrinsic enzymatic activity but acts as a multifunctional regulatory scaffold: it binds the αIIb integrin cytoplasmic tail (via a C-terminal hydrophobic pocket) to competitively inhibit talin-mediated integrin αIIbbeta3 activation and regulate outside-in signaling and platelet spreading; it directly activates PAK1 in a Ca2+-dependent manner to control cofilin phosphorylation and cell migration; it anchors calcineurin to the sarcolemma via calcineurin B interaction to regulate pathological cardiac hypertrophy; it inhibits ASK1 autophosphorylation to suppress stress-activated MAPK signaling in a Ca2+-sensitive fashion; it modulates InsP3 receptor gating; it facilitates plasma membrane localization of sphingosine kinase 1 to promote oncogenic Ras signaling; it supports PI3K/AKT and MEK/ERK survival signaling in cancer cells; it forms a complex with EVER1/EVER2 in keratinocytes to mediate intrinsic immunity against beta-papillomaviruses; and it is itself subject to proteasomal degradation via CHIP-mediated ubiquitination at Lys10 and Lys65.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"CIB1 is a calcium- and integrin-binding protein that functions as a multifunctional regulatory scaffold, coupling Ca²⁺ sensing to integrin signaling, kinase regulation, ion channel modulation, and innate immunity. Structurally, CIB1 is a compact, predominantly monomeric α-helical protein with four EF-hands (the C-terminal pair binding Ca²⁺) and a conserved hydrophobic pocket that engages the αIIb integrin cytoplasmic tail to competitively inhibit talin-mediated inside-out integrin activation while promoting outside-in signaling required for platelet spreading and stable thrombus formation [PMID:15574431, PMID:16418530, PMID:19691476]. CIB1 directly activates PAK1 in a Ca²⁺-dependent manner to regulate cofilin phosphorylation, cell migration, and angiogenesis; inhibits ASK1 autophosphorylation to suppress stress-activated MAPK signaling; anchors calcineurin to the sarcolemma to drive pathological cardiac hypertrophy; modulates InsP3 receptor gating and Ca²⁺ release; and facilitates sphingosine kinase 1 plasma membrane translocation to support oncogenic Ras signaling [PMID:16061695, PMID:19805025, PMID:20639889, PMID:16723353, PMID:27941888]. Loss-of-function mutations in CIB1 cause epidermodysplasia verruciformis with selective susceptibility to β-papillomaviruses, reflecting its role as a subunit of the EVER1/EVER2 restriction factor complex in keratinocytes [PMID:30068544].\",\n  \"teleology\": [\n    {\n      \"year\": 1999,\n      \"claim\": \"Establishing CIB1 as a direct, Ca²⁺-dependent binding partner of the αIIb integrin cytoplasmic domain answered whether this novel calcineurin-B-like protein had a specific receptor target in platelets.\",\n      \"evidence\": \"Isothermal titration calorimetry measuring 1:1 stoichiometry and ~700 nM Kd, plus yeast two-hybrid and co-fractionation with αIIbβ3 in activated platelets\",\n      \"pmids\": [\"10477286\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional consequence of αIIb binding in platelets not yet demonstrated\", \"Whether CIB1 binds other integrin α-subunits unknown\"]\n    },\n    {\n      \"year\": 2002,\n      \"claim\": \"Mapping the CIB1-integrin interface to the C-terminal hydrophobic pocket established the structural basis for ligand recognition, showing CIB1 uses a calmodulin/calcineurin-B-like target-binding mode.\",\n      \"evidence\": \"Systematic alanine scanning mutagenesis of 12 hydrophobic pocket residues with tryptophan fluorescence binding assay and CD confirmation of fold integrity\",\n      \"pmids\": [\"12023286\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Atomic-resolution structure of the CIB1–αIIb complex not yet determined\", \"Whether the same pocket engages non-integrin partners unknown\"]\n    },\n    {\n      \"year\": 2003,\n      \"claim\": \"Demonstrating that CIB1 is required for platelet lamellipodia formation during outside-in signaling resolved whether the CIB1–αIIbβ3 interaction had functional significance beyond binding.\",\n      \"evidence\": \"Co-IP of endogenous proteins during fibrinogen adhesion; intracellular anti-CIB antibody and peptide inhibition block spreading; recombinant CIB1 rescues the phenotype\",\n      \"pmids\": [\"12714504\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Downstream signaling intermediates linking CIB1 to cytoskeletal reorganization not defined\", \"In vivo platelet function in CIB1-null animals not yet tested\"]\n    },\n    {\n      \"year\": 2004,\n      \"claim\": \"The 2.0 Å crystal structure of Ca²⁺-bound CIB1 revealed four EF-hands with only the C-terminal pair competent for Ca²⁺ binding, a calcineurin-B-like fold, and a monomeric state, providing the first atomic framework for understanding CIB1 partner recognition.\",\n      \"evidence\": \"X-ray crystallography at 2.0 Å resolution with CD and mutagenesis validation\",\n      \"pmids\": [\"15574431\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Apo- and Mg²⁺-bound structures not yet available\", \"Structural basis for discrimination among partners unresolved\"]\n    },\n    {\n      \"year\": 2005,\n      \"claim\": \"Identification of PAK1 as a direct CIB1-activated kinase established CIB1 as an upstream regulator of the PAK1–LIMK–cofilin axis controlling cell migration, extending its role beyond integrins.\",\n      \"evidence\": \"In vitro kinase activation assay, co-IP, reciprocal overexpression/RNAi with migration and cofilin phosphorylation readouts\",\n      \"pmids\": [\"16061695\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether CIB1 activates PAK1 in platelets specifically unknown\", \"Structural basis of PAK1 activation by CIB1 not determined\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Showing that CIB1 competitively inhibits talin binding to αIIb to suppress inside-out integrin activation resolved the paradox of CIB1 promoting outside-in but restraining inside-out signaling, establishing CIB1 as a bidirectional integrin regulator.\",\n      \"evidence\": \"Overexpression blocks and RNAi enhances agonist-induced αIIbβ3 activation in megakaryocytes; competition binding with talin\",\n      \"pmids\": [\"16418530\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In vivo consequence in CIB1-null platelets not yet shown at this time\", \"Whether CIB1 regulates other integrin α-subunit activation in non-platelet cells untested\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"CIB1 binding to InsP3 receptors and direct activation of channel gating demonstrated a second Ca²⁺-regulatory function, linking CIB1 to intracellular Ca²⁺ store mobilization.\",\n      \"evidence\": \"Single-channel patch clamp showing CIB1 opens InsP3R without InsP3; EF-hand mutants lose binding; overexpression attenuates InsP3R-dependent Ca²⁺ signaling\",\n      \"pmids\": [\"16723353\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological context where CIB1–InsP3R interaction dominates undefined\", \"Whether CIB1 modulates store-operated Ca²⁺ entry indirectly not tested\"]\n    },\n    {\n      \"year\": 2006,\n      \"claim\": \"Cib1⁻/⁻ male sterility due to disrupted spermatogenesis revealed an essential developmental role for CIB1 beyond platelets and signaling.\",\n      \"evidence\": \"Germline knockout with histological loss of elongated spermatids, increased germ cell apoptosis, and elevated Cdk1 expression\",\n      \"pmids\": [\"16982698\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular mechanism linking CIB1 loss to spermatogenic arrest not defined\", \"Whether PAK1 or integrin pathways mediate this phenotype untested\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Cib1⁻/⁻ mice confirmed CIB1 is required in vivo for stable thrombus formation and outside-in (but not inside-out) integrin signaling, validating earlier cell-based findings.\",\n      \"evidence\": \"Extended tail bleeding, unstable thrombi by intravital microscopy, reduced β3 phosphorylation and spreading ex vivo, normal aggregation\",\n      \"pmids\": [\"19691476\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Compensatory upregulation of CIB3 may mask full phenotype\", \"Mechanism connecting CIB1 to β3 tyrosine phosphorylation not resolved\"]\n    },\n    {\n      \"year\": 2007,\n      \"claim\": \"Extension of the CIB1–PAK1 axis to angiogenesis demonstrated that CIB1 regulates endothelial cell migration, proliferation, and in vivo neovascularization through PAK1–ERK1/2–MMP2 signaling.\",\n      \"evidence\": \"shRNA and Cib1⁻/⁻ mice with impaired ischemia-induced angiogenesis; reduced PAK1 and ERK1/2 activation and MMP-2 expression in endothelial cells\",\n      \"pmids\": [\"17975111\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether CIB1's integrin-regulatory and PAK1-activating roles are separable in endothelial cells unknown\", \"Therapeutic targeting implications not tested\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"CIB1 binding to ASK1 and inhibition of its autophosphorylation, reversed by Ca²⁺ influx, established CIB1 as a Ca²⁺-sensitive brake on stress-activated MAPK signaling and cell death.\",\n      \"evidence\": \"Co-IP, in vitro kinase assay showing inhibition of Thr-838 autophosphorylation, TRAF2 displacement, Ca²⁺-dependent relief in dopaminergic neurons\",\n      \"pmids\": [\"19805025\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"In vivo relevance in neurodegeneration not tested with Cib1⁻/⁻ mice\", \"Whether CIB1–ASK1 is relevant outside neuronal cells untested\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"CIB1 anchoring calcineurin to the sarcolemma to drive pathological cardiac hypertrophy, demonstrated by genetic epistasis with calcineurin Aβ, placed CIB1 as a critical spatial regulator of calcineurin-NFAT signaling in the heart.\",\n      \"evidence\": \"Cib1⁻/⁻ mice resist pressure-overload hypertrophy; cardiac CIB1 transgenic enhances hypertrophy unless calcineurin Aβ is deleted; yeast two-hybrid with calcineurin B; sarcolemmal localization by fractionation\",\n      \"pmids\": [\"20639889\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether CIB1 regulates calcineurin in non-cardiac tissues unknown\", \"Structural basis of CIB1–calcineurin B interaction not determined\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Solution NMR structures revealed that EF-hand III directly contacts the αIIb tail and the C-terminal helix is displaced upon binding, providing the first dynamic picture of the CIB1–integrin interaction.\",\n      \"evidence\": \"NMR chemical shift perturbation and backbone amide dynamics for Ca²⁺-CIB1 and Mg²⁺-CIB1 ± αIIb peptide\",\n      \"pmids\": [\"21388953\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Full NMR structure of the CIB1–αIIb complex not determined\", \"How divalent cation state switches partner selectivity not fully explained\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Extension of CIB1 binding to multiple α-integrin cytoplasmic tails via a conserved consensus motif broadened CIB1 from a platelet-specific to a general integrin regulator.\",\n      \"evidence\": \"Computational docking validated by co-IP and competitive binding assays for multiple α-integrins\",\n      \"pmids\": [\"24011356\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequence of CIB1 binding to non-αIIb integrins not established in vivo\", \"Whether CIB1 regulates inside-out activation for all bound integrins untested\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"CIB1's Ca²⁺-myristoyl switch facilitating sphingosine kinase 1 plasma membrane translocation and oncogenic Ras signaling established CIB1 as a lipid signaling scaffold with transforming potential.\",\n      \"evidence\": \"CIB1 overexpression drives SK1 to plasma membrane and induces transformation in a SK1-dependent manner; CIB1 knockdown suppresses Ras-driven neoplastic growth\",\n      \"pmids\": [\"27941888\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether the myristoyl switch is required for all CIB1 membrane-associated functions untested\", \"In vivo tumor model with genetic CIB1 loss not performed\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"CIB1 interaction with type III CD38 and regulation of cADPR synthesis revealed an unexpected role in NAD⁺ metabolite signaling.\",\n      \"evidence\": \"Multiple interaction methods (Y2H, co-IP, BiFC, ELISA); CRISPR knockout reduces cellular cADPR\",\n      \"pmids\": [\"28720704\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological consequence of altered cADPR levels upon CIB1 loss not characterized\", \"Whether this pathway intersects CIB1's Ca²⁺ regulatory functions unknown\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Human loss-of-function CIB1 mutations causing epidermodysplasia verruciformis, and CIB1 forming a complex with EVER1/EVER2, established CIB1 as an essential component of intrinsic anti-HPV immunity in keratinocytes.\",\n      \"evidence\": \"Patient null mutations; CIB1 protein lost in EVER1/EVER2-deficient cells; co-IP of CIB1–EVER1/EVER2 complex; CIB1 interacts with HPV E5 and E8\",\n      \"pmids\": [\"30068544\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism by which CIB1–EVER complex restricts β-HPV replication not defined\", \"Whether CIB1's Ca²⁺-binding activity is required for antiviral function untested\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"CHIP-mediated polyubiquitination of CIB1 at Lys10 and Lys65 targeting it for proteasomal degradation defined the first regulated turnover mechanism for CIB1, with functional consequences for EMT and metastasis.\",\n      \"evidence\": \"Mass spectrometry interactome, co-IP, ubiquitination assay with K10R/K65R mutants, in vivo metastasis assay\",\n      \"pmids\": [\"33082516\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Signals triggering CHIP-mediated CIB1 degradation not identified\", \"Whether other E3 ligases also regulate CIB1 stability unknown\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How CIB1 discriminates among its diverse binding partners in a context-dependent manner, and whether its Ca²⁺-myristoyl switch is universally required for membrane-associated functions, remain major unresolved questions.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No co-crystal or cryo-EM structure of CIB1 bound to any full-length partner\", \"Integrated model of how Ca²⁺ concentration switches CIB1 between inhibitory and activating modes lacking\", \"Whether CIB1 family members (CIB2–4) are functionally redundant in vivo not systematically tested\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [4, 6, 7, 9, 10, 12, 18]},\n      {\"term_id\": \"GO:0008289\", \"supporting_discovery_ids\": [0, 1, 2]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [8, 18, 20]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [5, 8, 18]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [19]},\n      {\"term_id\": \"GO:0005856\", \"supporting_discovery_ids\": [2, 5]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-109582\", \"supporting_discovery_ids\": [4, 5, 15]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [6, 7, 8, 17, 18]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [20]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [14, 16]}\n    ],\n    \"complexes\": [\n      \"EVER1/EVER2/CIB1 complex\"\n    ],\n    \"partners\": [\n      \"ITGA2B\",\n      \"PAK1\",\n      \"ASK1\",\n      \"PPP3CB\",\n      \"SPHK1\",\n      \"ITPR1\",\n      \"CD38\",\n      \"STUB1\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}