{"gene":"GSKIP","run_date":"2026-06-10T01:55:21","timeline":{"discoveries":[{"year":2006,"finding":"GSKIP was identified as a GSK3β-binding protein via yeast two-hybrid screen; a 25-amino acid C-terminal region of GSKIP is highly similar to the GSK3β interaction domain (GID) of Axin. In vitro kinase assays showed GSKIP is a GSK3β substrate and that both full-length GSKIP and its C-terminal fragment block phosphorylation of primed and non-primed GSK3β substrates. A synthetic GSKIPtide competes with and blocks phosphorylation of Axin and β-catenin by GSK3β. Overexpression of GSKIP induces β-catenin accumulation in cytoplasm and nucleus and activates Tcf-4 transcriptional activity, defining GSKIP as a negative regulator of GSK3β in the Wnt signaling pathway.","method":"Yeast two-hybrid screen, in vitro kinase assay, peptide competition assay, immunofluorescence, Tcf-4 reporter assay","journal":"Biochemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — multiple orthogonal methods (yeast two-hybrid, in vitro kinase assay, peptide competition, reporter assay) in a single focused mechanistic study","pmids":["16981698"],"is_preprint":false},{"year":2009,"finding":"GSKIP binding to GSK3β shares overlapping sites (scaffold-binding region I, SBR-I residues 260–300) with AxinGID and FRATtide, as mapped by single-point mutations in GSK3β. GSK3β V267G mutation reduces binding to GSKIP and AxinGID but not FRATtide, while Y288F mutation abolishes FRATtide binding without affecting GSKIP or AxinGID. A novel C-terminal helix region of GSK3β (SBR-II, residues 339–383) is required for FRATtide binding but not GSKIP or AxinGID binding.","method":"GSK3β single-point mutagenesis, co-immunoprecipitation/binding assays, molecular simulation","journal":"Molecular and cellular biochemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — site-directed mutagenesis with binding assays and computational validation, single lab","pmids":["20043192"],"is_preprint":false},{"year":2009,"finding":"In SH-SY5Y neuroblastoma cells, GSKIP overexpression prevents neurite outgrowth, inhibits GSK3β-mediated phosphorylation of tau at Ser396, increases nuclear β-catenin and cyclin D1 levels, and downregulates N-cadherin expression, reducing recruitment of β-catenin to the membrane. siRNA depletion of β-catenin blocks neurite outgrowth, establishing GSKIP as a regulator of the GSK3β/β-catenin and N-cadherin/β-catenin pools during neuronal differentiation.","method":"Overexpression, siRNA knockdown, immunofluorescence, Western blotting in SH-SY5Y cells with retinoic acid differentiation","journal":"Journal of cellular biochemistry","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — loss-of-function and gain-of-function with multiple molecular readouts, single lab","pmids":["19830702"],"is_preprint":false},{"year":2011,"finding":"Molecular dynamics simulation of GSK3β complexed with a peptide derived from GSKIP (GSKIPtide) showed that GSKIPtide binds a hydrophobic pocket formed by an α-helix and an extended loop near the GSK3β C-terminus; this binding mode is closer to AxinGID than to FRATtide. V267G mutation in GSK3β reduces GSKIPtide binding affinity by ~70%, and Y288F abolishes FRATtide binding but does not affect GSKIPtide, consistent with experimental mutagenesis data.","method":"Molecular dynamics simulation validated against experimental mutagenesis data","journal":"Biopolymers","confidence":"Low","confidence_rationale":"Tier 4 / Weak — computational prediction validated only against prior experimental data, no new in vitro assay","pmids":["21328310"],"is_preprint":false},{"year":2015,"finding":"GSKIP forms a working complex PKA/GSKIP/GSK3β/Drp1 that mediates Drp1 Ser637 phosphorylation in the cAMP/PKA/Drp1 axis. GSKIP wild-type overexpression increases Drp1 S637 phosphorylation 7–8-fold versus PKA-binding-defective (V41/L45) and GSK3β-binding-defective (L130) GSKIP mutants under H2O2/forskolin challenge. Silencing either GSKIP or GSK3β (but not GSK3α) dramatically reduces Drp1 S637 phosphorylation. Kinase-dead GSK3β-K85R (retains GSKIP binding) sustains Drp1 phosphorylation, whereas K85M (loses GSKIP binding) does not, indicating GSK3β acts as an anchoring protein rather than a kinase in this complex. Phosphomimetic Drp1 S637D (but not S637A) rescues the elongated mitochondrial morphology lost in GSKIP mutant-overexpressing cells, placing Drp1 downstream of PKA/GSKIP/GSK3β signaling.","method":"Site-directed mutagenesis, overexpression, siRNA knockdown, phosphorylation assays, mitochondrial morphology imaging in HEK293 cells","journal":"Biochimica et biophysica acta","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal loss-of-function (siRNA) and gain-of-function (mutants), phosphomimetic rescue, multiple orthogonal methods in one rigorous study","pmids":["25920809"],"is_preprint":false},{"year":2015,"finding":"GSKIP deficiency in a conditional knockout mouse causes lethality at birth with cleft palate and delayed ossification. At the molecular level, GSKIP loss decreases GSK3β phosphorylation at Ser-9 (starting at E10.5), leading to enhanced GSK3β activity, establishing GSKIP as an in vivo regulator of GSK3β activity required for palatal shelf fusion.","method":"Conditional knockout mouse model, immunohistochemistry, Western blotting for GSK3β Ser-9 phosphorylation","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — clean in vivo KO with defined molecular phenotype (GSK3β Ser-9 phosphorylation) and developmental readout, characterization across multiple embryonic stages","pmids":["26582204"],"is_preprint":false},{"year":2015,"finding":"Germline duplication of GSKIP (and ATG2B) enhances hematopoietic progenitor differentiation, including megakaryocyte differentiation, by increasing progenitor sensitivity to thrombopoietin (TPO), and cooperates with acquired JAK2, MPL, and CALR mutations during myeloproliferative neoplasm development, as demonstrated in iPSC and primary cell models.","method":"Induced pluripotent stem cell (iPSC) models, primary hematopoietic cell assays, genetic epistasis with JAK2/MPL/CALR mutations","journal":"Nature genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — iPSC and primary cell functional assays, single lab, epistasis with signaling mutations","pmids":["26280900"],"is_preprint":false},{"year":2016,"finding":"GSKIP functions as an AKAP that simultaneously binds PKA and GSK3β, and both interactions are required for regulation of β-catenin. GSKIP facilitates PKA-mediated stabilizing phosphorylation of β-catenin at Ser-675 and facilitates GSK3β-mediated destabilizing phosphorylation at Ser-33/Ser-37/Thr-41. GSKIP acts as a scavenger that recruits PKA and GSK3β away from the β-catenin destruction complex without forming a complex with β-catenin itself. AKAP220, which also binds PKA and GSK3β via a conserved GID, did not affect Wnt signaling, indicating specificity of the GSKIP mechanism.","method":"Mutant overexpression (PKA-binding and GSK3β-binding defective GSKIP), co-immunoprecipitation, phosphorylation assays, Wnt reporter assays, comparison with AKAP220","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (Co-IP, phosphorylation assays, reporter assays, domain mutants, specificity control with AKAP220), single lab rigorous study","pmids":["27484798"],"is_preprint":false},{"year":2018,"finding":"The PKA-RII binding domain (V41/L45 residues) of GSKIP is required for forming the PKA/GSKIP/GSK3β/Drp1 working complex and for Drp1 Ser637 phosphorylation. Yeast two-hybrid and co-immunoprecipitation show the V41/L45P mutant causes a gain-of-function in GSKIP dimerization that further influences GSK3β binding, while L130 (GSK3β-binding site) mediates GSKIP dimerization. Molecular modeling indicates mammalian GSKIP can form a dimer through the L130 residue rather than V41/L45.","method":"Yeast two-hybrid, co-immunoprecipitation, site-directed mutagenesis, molecular modeling","journal":"Biochimica et biophysica acta. Molecular cell research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal yeast two-hybrid and Co-IP with mutagenesis, single lab","pmids":["29694914"],"is_preprint":false},{"year":2019,"finding":"GSKIP anchoring enhances PKA-mediated phosphorylation of Tau at Ser409; overexpression of GSKIP WT produces greater Tau Ser409 phosphorylation than PKA-binding-defective (V41/L45) or GSK3β-binding-defective (L130) mutants. In vitro kinase assays show that the combination of GSK3β with PKA (but not CaMKII) provides a conformational context for Tau Ser409 phosphorylation. In APPWT/D678H iPSC-derived cells, PKA-mediated Tau phosphorylation is enhanced relative to controls, implicating the cAMP/PKA/GSKIP/GSK3β axis in Alzheimer-relevant Tau hyperphosphorylation.","method":"In vitro kinase assay, overexpression of GSKIP mutants, CRISPR/Cas9 isogenic iPSC mutants, Western blotting","journal":"Journal of clinical medicine","confidence":"Medium","confidence_rationale":"Tier 1–2 / Moderate — in vitro kinase reconstitution plus iPSC cellular model with domain mutants, single lab","pmids":["31640277"],"is_preprint":false},{"year":2020,"finding":"GSKIP overexpression in cardiomyocytes subjected to hypoxia/reoxygenation (H/R) injury upregulates nuclear Nrf2 and increases Nrf2/ARE transcriptional activity associated with increased GSK3β Ser-9 phosphorylation (GSK3β inhibition). Pharmacological GSK3β inhibition rescues the phenotype caused by GSKIP depletion, placing GSKIP upstream of GSK3β in regulating Nrf2/ARE antioxidant signaling. Nrf2 inhibition reverses the cardioprotective effect of GSKIP overexpression.","method":"Overexpression, siRNA knockdown, pharmacological GSK3β inhibition, Nrf2/ARE reporter assay, Western blotting in cardiomyocytes","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — gain- and loss-of-function with epistatic pharmacological rescue, single lab","pmids":["32828530"],"is_preprint":false},{"year":2021,"finding":"Double knockout of Atg2b and Gskip (but not either gene alone) in mice causes severely decreased hematopoiesis, reduction in long-term HSC pool size due to increased cell death, and lethality in utero with anemia. Loss of both genes increases expression of oxidative phosphorylation genes without affecting autophagy, revealing a synergistic role for GSKIP and ATG2B in HSC maintenance through a non-autophagy mechanism.","method":"Double and single knockout mouse models, flow cytometry of HSC populations, bone marrow/fetal liver analysis, transcriptomic gene expression","journal":"Molecular and cellular biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean double-KO genetic epistasis with defined HSC phenotype and molecular readout, single lab","pmids":["34748402"],"is_preprint":false},{"year":2023,"finding":"CRISPR/Cas9 knockout of GSKIP in SH-SY5Y cells produces a cell aggregation phenotype and reduced cell growth via suppression of GSK3β/β-catenin pathways and cell cycle progression, linked to EMT/MET signaling rather than differentiation. Phosphorylated β-catenin at S675 and S552 (but not S33/S37/T41) translocates to the nucleus in GSKIP-KO cells. Reintroduction of GSKIP into KO cells restores cell migration and tumorigenesis, and neurite outgrowth upon RA treatment is still observed in GSKIP-KO clones.","method":"CRISPR/Cas9 knockout, rescue by GSKIP re-expression, gene set enrichment analysis, Western blotting for β-catenin phosphorylation, migration assays","journal":"Journal of cell communication and signaling","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — CRISPR KO with rescue experiment and multiple molecular readouts, single lab","pmids":["37133713"],"is_preprint":false}],"current_model":"GSKIP is a small cytosolic A-kinase anchoring protein (AKAP) that simultaneously binds PKA (via its N-terminal PKA-RII domain, residues V41/L45) and GSK3β (via its C-terminal GID-like domain, residue L130), functioning as a scaffolding scavenger that recruits both kinases away from the β-catenin destruction complex to regulate canonical Wnt/β-catenin signaling; it also organizes a PKA/GSKIP/GSK3β/Drp1 complex to promote PKA-mediated Drp1 Ser637 phosphorylation and mitochondrial elongation, facilitates PKA-dependent Tau phosphorylation, and in vivo controls GSK3β Ser-9 phosphorylation (activity) to support palatal shelf fusion and hematopoietic stem cell maintenance."},"narrative":{"mechanistic_narrative":"GSKIP is a small cytosolic A-kinase anchoring protein (AKAP) that functions as a dual-kinase scaffold and negative regulator of GSK3β signaling [PMID:16981698, PMID:27484798]. It was first identified as a GSK3β-binding protein bearing a C-terminal GID-like region homologous to the Axin GSK3β-interaction domain; through this region GSKIP competitively blocks GSK3β phosphorylation of primed and non-primed substrates including Axin and β-catenin, driving β-catenin accumulation and Tcf-4 transcriptional activation in the Wnt pathway [PMID:16981698]. This GID-like binding engages GSK3β at sites overlapping those used by Axin but distinct from FRATtide, defining its mode of recognition [PMID:20043192]. As an AKAP, GSKIP simultaneously binds PKA (via its N-terminal PKA-RII docking residues V41/L45) and GSK3β (via residue L130), and both interactions are required for it to act as a scavenger that recruits the two kinases away from the β-catenin destruction complex, coordinating PKA-mediated stabilizing phosphorylation of β-catenin (Ser-675) and GSK3β-mediated destabilizing phosphorylation (Ser-33/Ser-37/Thr-41) without itself joining the destruction complex [PMID:27484798]. The same dual-anchoring architecture assembles a PKA/GSKIP/GSK3β/Drp1 complex in which GSK3β serves a structural rather than catalytic role to promote PKA phosphorylation of Drp1 at Ser637 and consequent mitochondrial elongation [PMID:25920809], and likewise potentiates PKA-mediated Tau phosphorylation at Ser409 [PMID:31640277]. In vivo, GSKIP controls GSK3β Ser-9 phosphorylation (and thus GSK3β activity), and its loss causes perinatal lethality with cleft palate and delayed ossification [PMID:26582204]; together with ATG2B it is required for hematopoietic stem cell maintenance [PMID:34748402]. GSKIP also modulates Nrf2/ARE antioxidant signaling upstream of GSK3β [PMID:32828530] and supports cell migration and EMT/MET-linked growth through the GSK3β/β-catenin axis [PMID:37133713].","teleology":[{"year":2006,"claim":"Established GSKIP as a GSK3β-binding protein and negative regulator of GSK3β, answering whether a dedicated cytosolic inhibitor of GSK3β substrate phosphorylation exists.","evidence":"Yeast two-hybrid screen, in vitro kinase and peptide competition assays, Tcf-4 reporter in cells","pmids":["16981698"],"confidence":"High","gaps":["Did not define how GSKIP itself is regulated","PKA-anchoring function not yet known","In vivo relevance untested"]},{"year":2009,"claim":"Mapped the GSK3β surface used by GSKIP, showing it overlaps the Axin GID site but is distinct from FRATtide, clarifying the structural basis of recognition.","evidence":"GSK3β single-point mutagenesis, binding assays and molecular simulation","pmids":["20043192"],"confidence":"Medium","gaps":["No high-resolution structure of the complex","Functional consequence of distinct binding modes unresolved"]},{"year":2009,"claim":"Connected GSKIP to neuronal differentiation by showing it controls GSK3β/β-catenin and N-cadherin/β-catenin pools, extending its regulatory role to a cellular phenotype.","evidence":"Overexpression and siRNA with immunofluorescence/Western in differentiating SH-SY5Y cells","pmids":["19830702"],"confidence":"Medium","gaps":["Mechanism linking β-catenin pools to neurite outgrowth not fully resolved","PKA contribution not examined"]},{"year":2011,"claim":"Provided an atomistic binding model for GSKIPtide on GSK3β, supporting an Axin-like rather than FRAT-like binding mode.","evidence":"Molecular dynamics simulation validated against prior mutagenesis","pmids":["21328310"],"confidence":"Low","gaps":["Computational only, no new experimental assay","No crystallographic confirmation"]},{"year":2015,"claim":"Defined GSKIP as the organizer of a PKA/GSKIP/GSK3β/Drp1 complex driving Drp1 Ser637 phosphorylation and mitochondrial elongation, revealing a function beyond Wnt regulation.","evidence":"Domain mutants, siRNA, phosphomimetic rescue and mitochondrial imaging in HEK293 cells","pmids":["25920809"],"confidence":"High","gaps":["Subcellular site of complex assembly not localized","Whether GSKIP targets the complex to mitochondria unclear"]},{"year":2015,"claim":"Demonstrated in vivo that GSKIP maintains GSK3β Ser-9 phosphorylation required for palatal fusion, establishing a developmental requirement.","evidence":"Conditional knockout mouse with IHC and Western across embryonic stages","pmids":["26582204"],"confidence":"High","gaps":["Tissue-specific contributions not dissected","Link between Ser-9 regulation and ossification defect incomplete"]},{"year":2015,"claim":"Linked GSKIP germline duplication to enhanced hematopoietic differentiation and myeloproliferative neoplasm cooperation, implicating dosage in disease.","evidence":"iPSC and primary hematopoietic cell assays with genetic epistasis to JAK2/MPL/CALR","pmids":["26280900"],"confidence":"Medium","gaps":["GSKIP vs ATG2B contributions in the duplication not separated here","Molecular pathway to TPO sensitization unresolved"]},{"year":2016,"claim":"Resolved the dual-anchoring mechanism: GSKIP simultaneously binds PKA and GSK3β to scavenge both kinases from the β-catenin destruction complex, with AKAP220 as a specificity control.","evidence":"PKA- and GSK3β-binding-defective mutants, Co-IP, phosphorylation and Wnt reporter assays","pmids":["27484798"],"confidence":"High","gaps":["Stoichiometry of the scavenged pool unquantified","Dynamics of recruitment vs destruction complex not measured"]},{"year":2018,"claim":"Identified the PKA-RII binding residues V41/L45 as required for the Drp1 complex and uncovered GSKIP dimerization mediated by L130, refining the architecture of the scaffold.","evidence":"Yeast two-hybrid, Co-IP, mutagenesis and molecular modeling","pmids":["29694914"],"confidence":"Medium","gaps":["Physiological role of dimerization not established","No structure of the dimer"]},{"year":2019,"claim":"Showed GSKIP anchoring enhances PKA-mediated Tau Ser409 phosphorylation, connecting the cAMP/PKA/GSKIP/GSK3β axis to Alzheimer-relevant Tau modification.","evidence":"In vitro kinase reconstitution, GSKIP domain mutants and isogenic iPSC models","pmids":["31640277"],"confidence":"Medium","gaps":["In vivo Tau pathology not tested","Role of GSK3β conformational contribution incompletely defined"]},{"year":2020,"claim":"Placed GSKIP upstream of GSK3β in Nrf2/ARE antioxidant signaling, extending its regulatory reach to cardioprotection.","evidence":"Overexpression/siRNA with pharmacological GSK3β inhibition and Nrf2/ARE reporter in cardiomyocytes","pmids":["32828530"],"confidence":"Medium","gaps":["Direct molecular link from GSK3β to Nrf2 not delineated","In vivo cardiac relevance untested"]},{"year":2021,"claim":"Revealed a non-autophagy synergy between GSKIP and ATG2B in HSC maintenance, distinguishing their roles from the autophagy machinery.","evidence":"Single and double knockout mice with HSC flow cytometry and transcriptomics","pmids":["34748402"],"confidence":"Medium","gaps":["Molecular basis of the GSKIP-ATG2B synergy unknown","Link to oxidative phosphorylation gene upregulation mechanistically unresolved"]},{"year":2023,"claim":"CRISPR knockout linked GSKIP to GSK3β/β-catenin-driven cell growth, migration and EMT/MET via S675/S552 β-catenin phosphorylation, separating these effects from differentiation.","evidence":"CRISPR/Cas9 knockout with rescue, GSEA, β-catenin phospho-Western and migration assays in SH-SY5Y","pmids":["37133713"],"confidence":"Medium","gaps":["Tumorigenic relevance in vivo not established","Mechanism selecting S675/S552 over S33/S37/T41 unclear"]},{"year":null,"claim":"How GSKIP's spatial targeting and dimerization determine which downstream branch (Wnt/β-catenin, Drp1/mitochondrial, Tau, Nrf2, HSC) it engages in a given cell type remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structure of full-length GSKIP with both kinases bound","Cell-type determinants of branch selection unknown","Upstream regulation of GSKIP itself uncharacterized"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[0,4,7]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0,7]},{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[4,7,8]}],"localization":[{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[2,7]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0,7]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[5]}],"complexes":["PKA/GSKIP/GSK3β/Drp1 complex"],"partners":["GSK3B","PRKAR2 (PKA-RII)","DRP1","ATG2B"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9P0R6","full_name":"GSK3B-interacting protein","aliases":["GSK3beta interaction protein"],"length_aa":139,"mass_kda":15.6,"function":"A-kinase anchoring protein for GSK3B and PKA that regulates or facilitates their kinase activity towards their targets (PubMed:16981698, PubMed:25920809, PubMed:27484798). The ternary complex enhances Wnt-induced signaling by facilitating the GSK3B- and PKA-induced phosphorylation of beta-catenin leading to beta-catenin degradation and stabilization respectively (PubMed:16981698, PubMed:27484798). Upon cAMP activation, the ternary complex contributes to neuroprotection against oxidative stress-induced apoptosis by facilitating the PKA-induced phosphorylation of DML1 and PKA-induced inactivation of GSK3B (PubMed:25920809). During neurite outgrowth promotes neuron proliferation; while increases beta-catenin-induced transcriptional activity through GSK3B kinase activity inhibition, reduces N-cadherin level to promote cell cycle progression (PubMed:19830702)","subcellular_location":"Cytoplasm; Nucleus","url":"https://www.uniprot.org/uniprotkb/Q9P0R6/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/GSKIP","classification":"Not Classified","n_dependent_lines":0,"n_total_lines":1208,"dependency_fraction":0.0},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"GSK3A","stoichiometry":4.0},{"gene":"GSK3B","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/GSKIP","total_profiled":1310},"omim":[{"mim_id":"616605","title":"GSK3B-INTERACTING PROTEIN; GSKIP","url":"https://www.omim.org/entry/616605"},{"mim_id":"616604","title":"CHROMOSOME 14q32 DUPLICATION SYNDROME, 700-KB","url":"https://www.omim.org/entry/616604"},{"mim_id":"605004","title":"GLYCOGEN SYNTHASE KINASE 3-BETA; GSK3B","url":"https://www.omim.org/entry/605004"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Golgi apparatus","reliability":"Approved"},{"location":"Vesicles","reliability":"Approved"},{"location":"Nucleoli","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/GSKIP"},"hgnc":{"alias_symbol":[],"prev_symbol":["C14orf129"]},"alphafold":{"accession":"Q9P0R6","domains":[{"cath_id":"3.30.2280.10","chopping":"32-136","consensus_level":"high","plddt":94.1831,"start":32,"end":136}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9P0R6","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9P0R6-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9P0R6-F1-predicted_aligned_error_v6.png","plddt_mean":83.94},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=GSKIP","jax_strain_url":"https://www.jax.org/strain/search?query=GSKIP"},"sequence":{"accession":"Q9P0R6","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9P0R6.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9P0R6/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9P0R6"}},"corpus_meta":[{"pmid":"26280900","id":"PMC_26280900","title":"Germline duplication of ATG2B and GSKIP predisposes to familial myeloid malignancies.","date":"2015","source":"Nature genetics","url":"https://pubmed.ncbi.nlm.nih.gov/26280900","citation_count":104,"is_preprint":false},{"pmid":"16981698","id":"PMC_16981698","title":"GSKIP is homologous to the Axin GSK3beta interaction domain and functions as a negative regulator of GSK3beta.","date":"2006","source":"Biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/16981698","citation_count":41,"is_preprint":false},{"pmid":"27484798","id":"PMC_27484798","title":"The A-Kinase Anchoring Protein (AKAP) Glycogen Synthase Kinase 3β Interaction Protein (GSKIP) Regulates β-Catenin through Its Interactions with Both Protein Kinase A (PKA) and GSK3β.","date":"2016","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/27484798","citation_count":38,"is_preprint":false},{"pmid":"32682012","id":"PMC_32682012","title":"The long noncoding RNA OTUD6B-AS1 enhances cell proliferation and the invasion of hepatocellular carcinoma cells through modulating GSKIP/Wnt/β-catenin signalling via the sequestration of miR-664b-3p.","date":"2020","source":"Experimental cell research","url":"https://pubmed.ncbi.nlm.nih.gov/32682012","citation_count":35,"is_preprint":false},{"pmid":"25920809","id":"PMC_25920809","title":"GSKIP- and GSK3-mediated anchoring strengthens cAMP/PKA/Drp1 axis signaling in the regulation of mitochondrial elongation.","date":"2015","source":"Biochimica et biophysica acta","url":"https://pubmed.ncbi.nlm.nih.gov/25920809","citation_count":29,"is_preprint":false},{"pmid":"19830702","id":"PMC_19830702","title":"GSKIP, an inhibitor of GSK3beta, mediates the N-cadherin/beta-catenin pool in the differentiation of SH-SY5Y cells.","date":"2009","source":"Journal of cellular biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/19830702","citation_count":24,"is_preprint":false},{"pmid":"31640277","id":"PMC_31640277","title":"GSKIP-Mediated Anchoring Increases Phosphorylation of Tau by PKA but Not by GSK3beta via cAMP/PKA/GSKIP/GSK3/Tau Axis Signaling in Cerebrospinal Fluid and iPS Cells in Alzheimer Disease.","date":"2019","source":"Journal of clinical medicine","url":"https://pubmed.ncbi.nlm.nih.gov/31640277","citation_count":20,"is_preprint":false},{"pmid":"32547080","id":"PMC_32547080","title":"MiR-181c-5p Mitigates Tumorigenesis in Cervical Squamous Cell Carcinoma via Targeting Glycogen Synthase Kinase 3β Interaction Protein (GSKIP).","date":"2020","source":"OncoTargets and therapy","url":"https://pubmed.ncbi.nlm.nih.gov/32547080","citation_count":17,"is_preprint":false},{"pmid":"34172895","id":"PMC_34172895","title":"Germline ATG2B/GSKIP-containing 14q32 duplication predisposes to early clonal hematopoiesis leading to myeloid neoplasms.","date":"2021","source":"Leukemia","url":"https://pubmed.ncbi.nlm.nih.gov/34172895","citation_count":17,"is_preprint":false},{"pmid":"20043192","id":"PMC_20043192","title":"Involvement of the residues of GSKIP, AxinGID, and FRATtide in their binding with GSK3beta to unravel a novel C-terminal scaffold-binding region.","date":"2009","source":"Molecular and cellular biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/20043192","citation_count":15,"is_preprint":false},{"pmid":"21328310","id":"PMC_21328310","title":"Prediction of the binding mode between GSK3β and a peptide derived from GSKIP using molecular dynamics simulation.","date":"2011","source":"Biopolymers","url":"https://pubmed.ncbi.nlm.nih.gov/21328310","citation_count":14,"is_preprint":false},{"pmid":"26582204","id":"PMC_26582204","title":"The A-kinase Anchoring Protein GSKIP Regulates GSK3β Activity and Controls Palatal Shelf Fusion in Mice.","date":"2015","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/26582204","citation_count":13,"is_preprint":false},{"pmid":"27308616","id":"PMC_27308616","title":"ATG2B and GSKIP: 2 new genes predisposing to myeloid malignancies.","date":"2015","source":"Molecular & cellular oncology","url":"https://pubmed.ncbi.nlm.nih.gov/27308616","citation_count":11,"is_preprint":false},{"pmid":"29694914","id":"PMC_29694914","title":"The origin of GSKIP, a multifaceted regulatory factor in the mammalian Wnt pathway.","date":"2018","source":"Biochimica et biophysica acta. Molecular cell research","url":"https://pubmed.ncbi.nlm.nih.gov/29694914","citation_count":10,"is_preprint":false},{"pmid":"35728705","id":"PMC_35728705","title":"Many faces and functions of GSKIP: a temporospatial regulation view.","date":"2022","source":"Cellular signalling","url":"https://pubmed.ncbi.nlm.nih.gov/35728705","citation_count":8,"is_preprint":false},{"pmid":"34748402","id":"PMC_34748402","title":"Loss of Atg2b and Gskip Impairs the Maintenance of the Hematopoietic Stem Cell Pool Size.","date":"2021","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/34748402","citation_count":5,"is_preprint":false},{"pmid":"32828530","id":"PMC_32828530","title":"GSKIP protects cardiomyocytes from hypoxia/reoxygenation-induced injury by enhancing Nrf2 activation via GSK-3β inhibition.","date":"2020","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/32828530","citation_count":4,"is_preprint":false},{"pmid":"34573656","id":"PMC_34573656","title":"Variation in the Ovine Glycogen Synthase Kinase 3 Beta-Interaction Protein Gene (GSKIP) Affects Carcass and Growth Traits in Romney Sheep.","date":"2021","source":"Animals : an open access journal from MDPI","url":"https://pubmed.ncbi.nlm.nih.gov/34573656","citation_count":3,"is_preprint":false},{"pmid":"35051222","id":"PMC_35051222","title":"Deciphering the evolution of composite-type GSKIP in mitochondria and Wnt signaling pathways.","date":"2022","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/35051222","citation_count":2,"is_preprint":false},{"pmid":"37133713","id":"PMC_37133713","title":"GSKIP modulates cell aggregation through EMT/MET signaling rather than differentiation in SH-SY5Y human neuroblastoma cells.","date":"2023","source":"Journal of cell communication and signaling","url":"https://pubmed.ncbi.nlm.nih.gov/37133713","citation_count":0,"is_preprint":false},{"pmid":"39140083","id":"PMC_39140083","title":"MiR-181c-5p Mitigates Tumorigenesis in Cervical Squamous Cell Carcinoma via Targeting Glycogen Synthase Kinase 3β Interaction Protein (GSKIP) [Retraction].","date":"2024","source":"OncoTargets and therapy","url":"https://pubmed.ncbi.nlm.nih.gov/39140083","citation_count":0,"is_preprint":false},{"pmid":"42208322","id":"PMC_42208322","title":"MiR-181b-5p facilitates proliferation and migration by regulating GSKIP through ERK/AKT signaling pathways in gastric cancer.","date":"2026","source":"International immunopharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/42208322","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":13722,"output_tokens":4269,"usd":0.052601,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":12312,"output_tokens":4230,"usd":0.083655,"stage2_stop_reason":"end_turn"},"total_usd":0.136256,"stage1_batch_id":"msgbatch_01DUPACZi7AAWwuZiUjseQF4","stage2_batch_id":"msgbatch_018yt7chE3f48PEFtDwtj6AE","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2006,\n      \"finding\": \"GSKIP was identified as a GSK3β-binding protein via yeast two-hybrid screen; a 25-amino acid C-terminal region of GSKIP is highly similar to the GSK3β interaction domain (GID) of Axin. In vitro kinase assays showed GSKIP is a GSK3β substrate and that both full-length GSKIP and its C-terminal fragment block phosphorylation of primed and non-primed GSK3β substrates. A synthetic GSKIPtide competes with and blocks phosphorylation of Axin and β-catenin by GSK3β. Overexpression of GSKIP induces β-catenin accumulation in cytoplasm and nucleus and activates Tcf-4 transcriptional activity, defining GSKIP as a negative regulator of GSK3β in the Wnt signaling pathway.\",\n      \"method\": \"Yeast two-hybrid screen, in vitro kinase assay, peptide competition assay, immunofluorescence, Tcf-4 reporter assay\",\n      \"journal\": \"Biochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — multiple orthogonal methods (yeast two-hybrid, in vitro kinase assay, peptide competition, reporter assay) in a single focused mechanistic study\",\n      \"pmids\": [\"16981698\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"GSKIP binding to GSK3β shares overlapping sites (scaffold-binding region I, SBR-I residues 260–300) with AxinGID and FRATtide, as mapped by single-point mutations in GSK3β. GSK3β V267G mutation reduces binding to GSKIP and AxinGID but not FRATtide, while Y288F mutation abolishes FRATtide binding without affecting GSKIP or AxinGID. A novel C-terminal helix region of GSK3β (SBR-II, residues 339–383) is required for FRATtide binding but not GSKIP or AxinGID binding.\",\n      \"method\": \"GSK3β single-point mutagenesis, co-immunoprecipitation/binding assays, molecular simulation\",\n      \"journal\": \"Molecular and cellular biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — site-directed mutagenesis with binding assays and computational validation, single lab\",\n      \"pmids\": [\"20043192\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2009,\n      \"finding\": \"In SH-SY5Y neuroblastoma cells, GSKIP overexpression prevents neurite outgrowth, inhibits GSK3β-mediated phosphorylation of tau at Ser396, increases nuclear β-catenin and cyclin D1 levels, and downregulates N-cadherin expression, reducing recruitment of β-catenin to the membrane. siRNA depletion of β-catenin blocks neurite outgrowth, establishing GSKIP as a regulator of the GSK3β/β-catenin and N-cadherin/β-catenin pools during neuronal differentiation.\",\n      \"method\": \"Overexpression, siRNA knockdown, immunofluorescence, Western blotting in SH-SY5Y cells with retinoic acid differentiation\",\n      \"journal\": \"Journal of cellular biochemistry\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — loss-of-function and gain-of-function with multiple molecular readouts, single lab\",\n      \"pmids\": [\"19830702\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Molecular dynamics simulation of GSK3β complexed with a peptide derived from GSKIP (GSKIPtide) showed that GSKIPtide binds a hydrophobic pocket formed by an α-helix and an extended loop near the GSK3β C-terminus; this binding mode is closer to AxinGID than to FRATtide. V267G mutation in GSK3β reduces GSKIPtide binding affinity by ~70%, and Y288F abolishes FRATtide binding but does not affect GSKIPtide, consistent with experimental mutagenesis data.\",\n      \"method\": \"Molecular dynamics simulation validated against experimental mutagenesis data\",\n      \"journal\": \"Biopolymers\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 4 / Weak — computational prediction validated only against prior experimental data, no new in vitro assay\",\n      \"pmids\": [\"21328310\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"GSKIP forms a working complex PKA/GSKIP/GSK3β/Drp1 that mediates Drp1 Ser637 phosphorylation in the cAMP/PKA/Drp1 axis. GSKIP wild-type overexpression increases Drp1 S637 phosphorylation 7–8-fold versus PKA-binding-defective (V41/L45) and GSK3β-binding-defective (L130) GSKIP mutants under H2O2/forskolin challenge. Silencing either GSKIP or GSK3β (but not GSK3α) dramatically reduces Drp1 S637 phosphorylation. Kinase-dead GSK3β-K85R (retains GSKIP binding) sustains Drp1 phosphorylation, whereas K85M (loses GSKIP binding) does not, indicating GSK3β acts as an anchoring protein rather than a kinase in this complex. Phosphomimetic Drp1 S637D (but not S637A) rescues the elongated mitochondrial morphology lost in GSKIP mutant-overexpressing cells, placing Drp1 downstream of PKA/GSKIP/GSK3β signaling.\",\n      \"method\": \"Site-directed mutagenesis, overexpression, siRNA knockdown, phosphorylation assays, mitochondrial morphology imaging in HEK293 cells\",\n      \"journal\": \"Biochimica et biophysica acta\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal loss-of-function (siRNA) and gain-of-function (mutants), phosphomimetic rescue, multiple orthogonal methods in one rigorous study\",\n      \"pmids\": [\"25920809\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"GSKIP deficiency in a conditional knockout mouse causes lethality at birth with cleft palate and delayed ossification. At the molecular level, GSKIP loss decreases GSK3β phosphorylation at Ser-9 (starting at E10.5), leading to enhanced GSK3β activity, establishing GSKIP as an in vivo regulator of GSK3β activity required for palatal shelf fusion.\",\n      \"method\": \"Conditional knockout mouse model, immunohistochemistry, Western blotting for GSK3β Ser-9 phosphorylation\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — clean in vivo KO with defined molecular phenotype (GSK3β Ser-9 phosphorylation) and developmental readout, characterization across multiple embryonic stages\",\n      \"pmids\": [\"26582204\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"Germline duplication of GSKIP (and ATG2B) enhances hematopoietic progenitor differentiation, including megakaryocyte differentiation, by increasing progenitor sensitivity to thrombopoietin (TPO), and cooperates with acquired JAK2, MPL, and CALR mutations during myeloproliferative neoplasm development, as demonstrated in iPSC and primary cell models.\",\n      \"method\": \"Induced pluripotent stem cell (iPSC) models, primary hematopoietic cell assays, genetic epistasis with JAK2/MPL/CALR mutations\",\n      \"journal\": \"Nature genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — iPSC and primary cell functional assays, single lab, epistasis with signaling mutations\",\n      \"pmids\": [\"26280900\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"GSKIP functions as an AKAP that simultaneously binds PKA and GSK3β, and both interactions are required for regulation of β-catenin. GSKIP facilitates PKA-mediated stabilizing phosphorylation of β-catenin at Ser-675 and facilitates GSK3β-mediated destabilizing phosphorylation at Ser-33/Ser-37/Thr-41. GSKIP acts as a scavenger that recruits PKA and GSK3β away from the β-catenin destruction complex without forming a complex with β-catenin itself. AKAP220, which also binds PKA and GSK3β via a conserved GID, did not affect Wnt signaling, indicating specificity of the GSKIP mechanism.\",\n      \"method\": \"Mutant overexpression (PKA-binding and GSK3β-binding defective GSKIP), co-immunoprecipitation, phosphorylation assays, Wnt reporter assays, comparison with AKAP220\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (Co-IP, phosphorylation assays, reporter assays, domain mutants, specificity control with AKAP220), single lab rigorous study\",\n      \"pmids\": [\"27484798\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"The PKA-RII binding domain (V41/L45 residues) of GSKIP is required for forming the PKA/GSKIP/GSK3β/Drp1 working complex and for Drp1 Ser637 phosphorylation. Yeast two-hybrid and co-immunoprecipitation show the V41/L45P mutant causes a gain-of-function in GSKIP dimerization that further influences GSK3β binding, while L130 (GSK3β-binding site) mediates GSKIP dimerization. Molecular modeling indicates mammalian GSKIP can form a dimer through the L130 residue rather than V41/L45.\",\n      \"method\": \"Yeast two-hybrid, co-immunoprecipitation, site-directed mutagenesis, molecular modeling\",\n      \"journal\": \"Biochimica et biophysica acta. Molecular cell research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal yeast two-hybrid and Co-IP with mutagenesis, single lab\",\n      \"pmids\": [\"29694914\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"GSKIP anchoring enhances PKA-mediated phosphorylation of Tau at Ser409; overexpression of GSKIP WT produces greater Tau Ser409 phosphorylation than PKA-binding-defective (V41/L45) or GSK3β-binding-defective (L130) mutants. In vitro kinase assays show that the combination of GSK3β with PKA (but not CaMKII) provides a conformational context for Tau Ser409 phosphorylation. In APPWT/D678H iPSC-derived cells, PKA-mediated Tau phosphorylation is enhanced relative to controls, implicating the cAMP/PKA/GSKIP/GSK3β axis in Alzheimer-relevant Tau hyperphosphorylation.\",\n      \"method\": \"In vitro kinase assay, overexpression of GSKIP mutants, CRISPR/Cas9 isogenic iPSC mutants, Western blotting\",\n      \"journal\": \"Journal of clinical medicine\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1–2 / Moderate — in vitro kinase reconstitution plus iPSC cellular model with domain mutants, single lab\",\n      \"pmids\": [\"31640277\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"GSKIP overexpression in cardiomyocytes subjected to hypoxia/reoxygenation (H/R) injury upregulates nuclear Nrf2 and increases Nrf2/ARE transcriptional activity associated with increased GSK3β Ser-9 phosphorylation (GSK3β inhibition). Pharmacological GSK3β inhibition rescues the phenotype caused by GSKIP depletion, placing GSKIP upstream of GSK3β in regulating Nrf2/ARE antioxidant signaling. Nrf2 inhibition reverses the cardioprotective effect of GSKIP overexpression.\",\n      \"method\": \"Overexpression, siRNA knockdown, pharmacological GSK3β inhibition, Nrf2/ARE reporter assay, Western blotting in cardiomyocytes\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — gain- and loss-of-function with epistatic pharmacological rescue, single lab\",\n      \"pmids\": [\"32828530\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"Double knockout of Atg2b and Gskip (but not either gene alone) in mice causes severely decreased hematopoiesis, reduction in long-term HSC pool size due to increased cell death, and lethality in utero with anemia. Loss of both genes increases expression of oxidative phosphorylation genes without affecting autophagy, revealing a synergistic role for GSKIP and ATG2B in HSC maintenance through a non-autophagy mechanism.\",\n      \"method\": \"Double and single knockout mouse models, flow cytometry of HSC populations, bone marrow/fetal liver analysis, transcriptomic gene expression\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean double-KO genetic epistasis with defined HSC phenotype and molecular readout, single lab\",\n      \"pmids\": [\"34748402\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"CRISPR/Cas9 knockout of GSKIP in SH-SY5Y cells produces a cell aggregation phenotype and reduced cell growth via suppression of GSK3β/β-catenin pathways and cell cycle progression, linked to EMT/MET signaling rather than differentiation. Phosphorylated β-catenin at S675 and S552 (but not S33/S37/T41) translocates to the nucleus in GSKIP-KO cells. Reintroduction of GSKIP into KO cells restores cell migration and tumorigenesis, and neurite outgrowth upon RA treatment is still observed in GSKIP-KO clones.\",\n      \"method\": \"CRISPR/Cas9 knockout, rescue by GSKIP re-expression, gene set enrichment analysis, Western blotting for β-catenin phosphorylation, migration assays\",\n      \"journal\": \"Journal of cell communication and signaling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — CRISPR KO with rescue experiment and multiple molecular readouts, single lab\",\n      \"pmids\": [\"37133713\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"GSKIP is a small cytosolic A-kinase anchoring protein (AKAP) that simultaneously binds PKA (via its N-terminal PKA-RII domain, residues V41/L45) and GSK3β (via its C-terminal GID-like domain, residue L130), functioning as a scaffolding scavenger that recruits both kinases away from the β-catenin destruction complex to regulate canonical Wnt/β-catenin signaling; it also organizes a PKA/GSKIP/GSK3β/Drp1 complex to promote PKA-mediated Drp1 Ser637 phosphorylation and mitochondrial elongation, facilitates PKA-dependent Tau phosphorylation, and in vivo controls GSK3β Ser-9 phosphorylation (activity) to support palatal shelf fusion and hematopoietic stem cell maintenance.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"GSKIP is a small cytosolic A-kinase anchoring protein (AKAP) that functions as a dual-kinase scaffold and negative regulator of GSK3\\u03b2 signaling [#0, #7]. It was first identified as a GSK3\\u03b2-binding protein bearing a C-terminal GID-like region homologous to the Axin GSK3\\u03b2-interaction domain; through this region GSKIP competitively blocks GSK3\\u03b2 phosphorylation of primed and non-primed substrates including Axin and \\u03b2-catenin, driving \\u03b2-catenin accumulation and Tcf-4 transcriptional activation in the Wnt pathway [#0]. This GID-like binding engages GSK3\\u03b2 at sites overlapping those used by Axin but distinct from FRATtide, defining its mode of recognition [#1]. As an AKAP, GSKIP simultaneously binds PKA (via its N-terminal PKA-RII docking residues V41/L45) and GSK3\\u03b2 (via residue L130), and both interactions are required for it to act as a scavenger that recruits the two kinases away from the \\u03b2-catenin destruction complex, coordinating PKA-mediated stabilizing phosphorylation of \\u03b2-catenin (Ser-675) and GSK3\\u03b2-mediated destabilizing phosphorylation (Ser-33/Ser-37/Thr-41) without itself joining the destruction complex [#7]. The same dual-anchoring architecture assembles a PKA/GSKIP/GSK3\\u03b2/Drp1 complex in which GSK3\\u03b2 serves a structural rather than catalytic role to promote PKA phosphorylation of Drp1 at Ser637 and consequent mitochondrial elongation [#4], and likewise potentiates PKA-mediated Tau phosphorylation at Ser409 [#9]. In vivo, GSKIP controls GSK3\\u03b2 Ser-9 phosphorylation (and thus GSK3\\u03b2 activity), and its loss causes perinatal lethality with cleft palate and delayed ossification [#5]; together with ATG2B it is required for hematopoietic stem cell maintenance [#11]. GSKIP also modulates Nrf2/ARE antioxidant signaling upstream of GSK3\\u03b2 [#10] and supports cell migration and EMT/MET-linked growth through the GSK3\\u03b2/\\u03b2-catenin axis [#12].\",\n  \"teleology\": [\n    {\n      \"year\": 2006,\n      \"claim\": \"Established GSKIP as a GSK3\\u03b2-binding protein and negative regulator of GSK3\\u03b2, answering whether a dedicated cytosolic inhibitor of GSK3\\u03b2 substrate phosphorylation exists.\",\n      \"evidence\": \"Yeast two-hybrid screen, in vitro kinase and peptide competition assays, Tcf-4 reporter in cells\",\n      \"pmids\": [\"16981698\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define how GSKIP itself is regulated\", \"PKA-anchoring function not yet known\", \"In vivo relevance untested\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Mapped the GSK3\\u03b2 surface used by GSKIP, showing it overlaps the Axin GID site but is distinct from FRATtide, clarifying the structural basis of recognition.\",\n      \"evidence\": \"GSK3\\u03b2 single-point mutagenesis, binding assays and molecular simulation\",\n      \"pmids\": [\"20043192\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No high-resolution structure of the complex\", \"Functional consequence of distinct binding modes unresolved\"]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Connected GSKIP to neuronal differentiation by showing it controls GSK3\\u03b2/\\u03b2-catenin and N-cadherin/\\u03b2-catenin pools, extending its regulatory role to a cellular phenotype.\",\n      \"evidence\": \"Overexpression and siRNA with immunofluorescence/Western in differentiating SH-SY5Y cells\",\n      \"pmids\": [\"19830702\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism linking \\u03b2-catenin pools to neurite outgrowth not fully resolved\", \"PKA contribution not examined\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Provided an atomistic binding model for GSKIPtide on GSK3\\u03b2, supporting an Axin-like rather than FRAT-like binding mode.\",\n      \"evidence\": \"Molecular dynamics simulation validated against prior mutagenesis\",\n      \"pmids\": [\"21328310\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Computational only, no new experimental assay\", \"No crystallographic confirmation\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Defined GSKIP as the organizer of a PKA/GSKIP/GSK3\\u03b2/Drp1 complex driving Drp1 Ser637 phosphorylation and mitochondrial elongation, revealing a function beyond Wnt regulation.\",\n      \"evidence\": \"Domain mutants, siRNA, phosphomimetic rescue and mitochondrial imaging in HEK293 cells\",\n      \"pmids\": [\"25920809\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Subcellular site of complex assembly not localized\", \"Whether GSKIP targets the complex to mitochondria unclear\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Demonstrated in vivo that GSKIP maintains GSK3\\u03b2 Ser-9 phosphorylation required for palatal fusion, establishing a developmental requirement.\",\n      \"evidence\": \"Conditional knockout mouse with IHC and Western across embryonic stages\",\n      \"pmids\": [\"26582204\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Tissue-specific contributions not dissected\", \"Link between Ser-9 regulation and ossification defect incomplete\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Linked GSKIP germline duplication to enhanced hematopoietic differentiation and myeloproliferative neoplasm cooperation, implicating dosage in disease.\",\n      \"evidence\": \"iPSC and primary hematopoietic cell assays with genetic epistasis to JAK2/MPL/CALR\",\n      \"pmids\": [\"26280900\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"GSKIP vs ATG2B contributions in the duplication not separated here\", \"Molecular pathway to TPO sensitization unresolved\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Resolved the dual-anchoring mechanism: GSKIP simultaneously binds PKA and GSK3\\u03b2 to scavenge both kinases from the \\u03b2-catenin destruction complex, with AKAP220 as a specificity control.\",\n      \"evidence\": \"PKA- and GSK3\\u03b2-binding-defective mutants, Co-IP, phosphorylation and Wnt reporter assays\",\n      \"pmids\": [\"27484798\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Stoichiometry of the scavenged pool unquantified\", \"Dynamics of recruitment vs destruction complex not measured\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Identified the PKA-RII binding residues V41/L45 as required for the Drp1 complex and uncovered GSKIP dimerization mediated by L130, refining the architecture of the scaffold.\",\n      \"evidence\": \"Yeast two-hybrid, Co-IP, mutagenesis and molecular modeling\",\n      \"pmids\": [\"29694914\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Physiological role of dimerization not established\", \"No structure of the dimer\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Showed GSKIP anchoring enhances PKA-mediated Tau Ser409 phosphorylation, connecting the cAMP/PKA/GSKIP/GSK3\\u03b2 axis to Alzheimer-relevant Tau modification.\",\n      \"evidence\": \"In vitro kinase reconstitution, GSKIP domain mutants and isogenic iPSC models\",\n      \"pmids\": [\"31640277\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"In vivo Tau pathology not tested\", \"Role of GSK3\\u03b2 conformational contribution incompletely defined\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Placed GSKIP upstream of GSK3\\u03b2 in Nrf2/ARE antioxidant signaling, extending its regulatory reach to cardioprotection.\",\n      \"evidence\": \"Overexpression/siRNA with pharmacological GSK3\\u03b2 inhibition and Nrf2/ARE reporter in cardiomyocytes\",\n      \"pmids\": [\"32828530\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct molecular link from GSK3\\u03b2 to Nrf2 not delineated\", \"In vivo cardiac relevance untested\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Revealed a non-autophagy synergy between GSKIP and ATG2B in HSC maintenance, distinguishing their roles from the autophagy machinery.\",\n      \"evidence\": \"Single and double knockout mice with HSC flow cytometry and transcriptomics\",\n      \"pmids\": [\"34748402\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular basis of the GSKIP-ATG2B synergy unknown\", \"Link to oxidative phosphorylation gene upregulation mechanistically unresolved\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"CRISPR knockout linked GSKIP to GSK3\\u03b2/\\u03b2-catenin-driven cell growth, migration and EMT/MET via S675/S552 \\u03b2-catenin phosphorylation, separating these effects from differentiation.\",\n      \"evidence\": \"CRISPR/Cas9 knockout with rescue, GSEA, \\u03b2-catenin phospho-Western and migration assays in SH-SY5Y\",\n      \"pmids\": [\"37133713\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Tumorigenic relevance in vivo not established\", \"Mechanism selecting S675/S552 over S33/S37/T41 unclear\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How GSKIP's spatial targeting and dimerization determine which downstream branch (Wnt/\\u03b2-catenin, Drp1/mitochondrial, Tau, Nrf2, HSC) it engages in a given cell type remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structure of full-length GSKIP with both kinases bound\", \"Cell-type determinants of branch selection unknown\", \"Upstream regulation of GSKIP itself uncharacterized\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [0, 4, 7]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0, 7]},\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [4, 7, 8]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [2, 7]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0, 7]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [5]}\n    ],\n    \"complexes\": [\"PKA/GSKIP/GSK3\\u03b2/Drp1 complex\"],\n    \"partners\": [\"GSK3B\", \"PRKAR2 (PKA-RII)\", \"DRP1\", \"ATG2B\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}