{"gene":"CAMK1","run_date":"2026-06-09T22:57:17","timeline":{"discoveries":[{"year":2012,"finding":"Crystal structures of human CaMKIα (apo form and ATP-bound complexes) revealed that in the autoinhibited state, the activation segment adopts a helical conformation that together with the autoinhibitory segment constrains helices αC and αD in inactive conformations, sequesters Thr177 from phosphorylation, and occludes the substrate-binding site. In an ATP-bound active structure, the regulatory region is dissociated from the catalytic core and the catalytic site assumes an active conformation.","method":"X-ray crystallography of four structures of three CaMKIα truncates in apo and ATP-bound forms","journal":"PloS one","confidence":"High","confidence_rationale":"Tier 1 / Strong — multiple crystal structures with functional interpretation, multiple orthogonal structural states analyzed in one study","pmids":["23028635"],"is_preprint":false},{"year":2011,"finding":"CaMKI (but not CaMKIV) contributes to stimulation of WIPI-1 puncta formation at the onset of autophagy downstream of Ca2+/CaMKK signaling; siRNA-mediated knockdown of CaMKI reduced starvation-induced autophagosomal membrane formation independently of AMPKα1/α2.","method":"siRNA knockdown of CaMKI, automated high-throughput WIPI-1 puncta analysis, LC3 lipidation assays, pharmacological inhibitors (STO-609, KN-93)","journal":"Molecular pharmacology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean siRNA knockdown with defined cellular phenotype, multiple pharmacological controls, single lab","pmids":["21896713"],"is_preprint":false},{"year":2011,"finding":"Epac1 and Rap1, in response to cAMP, activate CaMKI to phosphorylate Ser47 of GCM1; this phosphorylation facilitates interaction between GCM1 and the desumoylating enzyme SENP1, leading to GCM1 desumoylation and activation, thereby promoting syncytin-1/2 expression and trophoblast cell fusion.","method":"RNAi knockdown, phosphomimetic/non-phosphorylatable GCM1 mutants, co-immunoprecipitation, transient expression assays in BeWo placental cells","journal":"Molecular and cellular biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal co-IP, phosphomimetic mutagenesis (S47D), RNAi rescue experiments, multiple orthogonal methods in one study","pmids":["21791615"],"is_preprint":false},{"year":2013,"finding":"The Epac1/Rap1/CaMKI signaling cascade phosphorylates HDAC5 on Ser259 and Ser498 in a Rap1- and CaMKI-dependent manner, causing nuclear export of HDAC5, thereby relieving HDAC5-mediated deacetylation and transcriptional repression of GCM1 and promoting syncytin-1 expression and placental cell fusion.","method":"Co-immunoprecipitation, immunofluorescence microscopy, phospho-specific antibodies against HDAC5, transient expression of constitutively active Epac1 and CaMKI, RNAi","journal":"Molecular human reproduction","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP, phospho-specific antibodies, constitutively active constructs, RNAi, multiple orthogonal methods, replicates the Epac1/CaMKI pathway from PMID:21791615","pmids":["23867755"],"is_preprint":false},{"year":2012,"finding":"CaMKI phosphorylates nuclear CaMK phosphatase (CaMKP-N/PPM1E; zebrafish ortholog zCaMKP-N) at Ser-480 in vitro; phosphorylation-mimic mutants (S480D/S480E) showed higher phosphatase activity and more potently attenuated CaMKII autophosphorylation in cells, indicating CaMKI activates CaMKP-N to provide negative feedback on multifunctional CaMKs.","method":"In vitro kinase assay with activated CaMKI, site-directed mutagenesis (S480A, S480D, S480E), solution-based phosphatase assay, co-transfection in Neuro2a cells with ionomycin treatment","journal":"Biochemical and biophysical research communications","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro kinase assay with mutagenesis, confirmed in cell-based assay, single lab but multiple orthogonal methods","pmids":["22627141"],"is_preprint":false},{"year":2015,"finding":"CaMKIδ isoform is phosphatase-resistant compared to CaMKIα due to its N-terminal region structure (residues Pro-57, Lys-62, Ser-66, Ile-68, and Arg-76); CaMKP/PPM1F barely dephosphorylates CaMKIδ, allowing it to remain in a 'primed' phosphorylated, active state under low-Ca2+ conditions and to phosphorylate CREB without Ca2+ stimulation.","method":"Transient expression in 293T cells, in vitro dephosphorylation assay with CaMKP/PPM1F, chimeric and point mutants of CaMKIδ and CaMKIα, CREB phosphorylation assay","journal":"Biochemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — in vitro enzymatic assay with systematic mutagenesis identifying causative residues, confirmed in cellular system, single lab","pmids":["25994484"],"is_preprint":false},{"year":2022,"finding":"Pitavastatin promotes mitochondrial calcium release into the cytoplasm, which phosphorylates CAMK1 (at Thr177); phosphorylated CAMK1 in turn phosphorylates PINK1 at Ser228, which recruits PARK2 (Parkin) and phosphorylates its Ser65 to activate mitophagy, improving endothelial progenitor cell proliferation.","method":"CAMK1 phosphorylation assays in EPCs, PINK1-KO mice, Atg7 silencing, intracellular calcium measurements, Western blot for phospho-CAMK1 (Thr177) and phospho-PINK1 (Ser228), pharmacological inhibition","journal":"Communications biology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — defined phosphorylation cascade with specific residues, genetic KO validation, single lab","pmids":["35145192"],"is_preprint":false},{"year":2021,"finding":"In C. elegans thermosensory neurons, elevation of intracellular Ca2+ is necessary and sufficient for CMK-1 (CaMKI ortholog) nuclear import; Ca2+/CaM binding to CMK-1 increases its affinity for IMA-3 importin, driving nuclear translocation with slow kinetics that matches the timescale of sensory adaptation and is essential for experience-dependent behavioral plasticity and gene transcription control.","method":"In vivo live imaging in C. elegans, genetic manipulation (loss-of-function, constitutively active CMK-1), optogenetics to control Ca2+, co-immunoprecipitation of CMK-1 with IMA-3 importin","journal":"eLife","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP, in vivo live imaging, multiple genetic manipulations, optogenetic control, functional behavioral readouts in a single rigorous study","pmids":["34766550"],"is_preprint":false},{"year":2015,"finding":"CMK-1 (CaMKI ortholog in C. elegans) regulates the dauer developmental decision as a function of feeding state; CMK-1 acts cell-autonomously in ASI neurons to regulate daf-7 TGF-β expression and non-cell-autonomously in AWC neurons to regulate daf-28 insulin-like peptide expression; food availability dynamically regulates subcellular localization of CMK-1 in AWC neurons.","method":"C. elegans genetics (cmk-1 mutants), cell-specific rescue experiments, transgenic reporters for daf-7 and daf-28, live imaging of CMK-1 subcellular localization","journal":"eLife","confidence":"High","confidence_rationale":"Tier 2 / Strong — cell-autonomous vs non-cell-autonomous genetic dissection, live subcellular localization, multiple neuronal circuit-level rescue experiments","pmids":["26335407"],"is_preprint":false},{"year":2018,"finding":"CMK-1 (CaMKI ortholog) is required in ASE chemosensory neurons for salt-aversive learning in C. elegans; loss of cmk-1 has subtle effects on sensory-evoked calcium responses in ASE axons and their modulation by salt conditioning, placing CMK-1 as a regulator of behavioral plasticity downstream of sensory calcium signals.","method":"C. elegans genetics (cmk-1 loss-of-function), microfluidics-based calcium imaging in ASE neurons, behavioral assays","journal":"The Journal of neuroscience","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — clean genetic loss-of-function with defined behavioral phenotype and calcium imaging, single lab","pmids":["29875264"],"is_preprint":false},{"year":2025,"finding":"In C. elegans, CMK-1 (CaMKI ortholog) and calcineurin TAX-6 have antagonistic roles in modulating thermal nociception and adaptation to repeated stimuli; in vitro kinase assay combined with phosphoproteomics identified hundreds of CMK-1 substrates including the calcineurin A subunit TAX-6 (phosphorylated in its conserved regulatory domain); cell-specific analysis placed CMK-1 in AFD and ASER neurons and TAX-6 in FLP neurons and interneurons.","method":"In vitro kinase assays, mass-spectrometry-based phosphoproteomics, C. elegans genetics, pharmacological analyses, cell-specific genetic manipulations","journal":"eLife","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — in vitro kinase assay with MS-based phosphoproteomics for substrate identification, genetic epistasis, but the direct TAX-6 phosphorylation may not underlie the behavioral phenotype as noted in the abstract","pmids":["40305390"],"is_preprint":false},{"year":2008,"finding":"Ca2+/calmodulin kinase I regulates Nur77 (Nr4a1) promoter activity in MA-10 Leydig cells; cAMP-mediated induction of Nur77 expression involves a CaMK-dependent pathway with distinct regulatory elements for basal and cAMP-induced Nur77 transcription.","method":"Promoter-reporter assays, pharmacological CaMK inhibition, transient transfection in MA-10 cells","journal":"Journal of andrology","confidence":"Low","confidence_rationale":"Tier 3 / Weak — promoter-reporter assays with pharmacological inhibition only, no direct CaMKI substrate identification or KD","pmids":["18835829"],"is_preprint":false},{"year":2005,"finding":"CKLiK (CaMKI-like kinase restricted to granulocytes) activity is induced by fMLP and PAF stimulation in parallel with intracellular Ca2+ rise; inhibition of CKLiK with a cell-permeable peptide inhibitor reduced phagocytosis, fMLP-induced ROS production, neutrophil migration, and β2-integrin-mediated adhesion.","method":"CKLiK peptide inhibitor (CKLiK297-321), kinase activity assays, phagocytosis assay, ROS/respiratory burst assay, migration assay, adhesion assay in primary human granulocytes","journal":"Blood","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple functional assays with a specific peptide inhibitor in primary human cells, defined cellular phenotypes, single lab","pmids":["15840691"],"is_preprint":false},{"year":2016,"finding":"A constitutively active fragment of zebrafish CaMKIδ (zCaMKIδ(1-299)) lacking the autoinhibitory domain showed high, Ca2+-independent kinase activity comparable to CaMKK-activated wild-type CaMKIδ, confirming that the autoinhibitory domain suppresses basal kinase activity; the fragment exhibited broad substrate specificity similar to full-length activated CaMKIδ.","method":"Recombinant protein expression in E. coli, in vitro kinase activity assays, substrate specificity profiling, comparison with PKAc and CaMKII","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 1 / Weak — in vitro reconstitution with deletion mutant confirming autoinhibitory mechanism, single lab, single study","pmids":["27207832"],"is_preprint":false},{"year":2024,"finding":"CAMK1 overexpression in colorectal cancer cells inhibits PI3K phosphorylation and downstream AKT pathway activation; CAMK1 interacts with PI3K (by co-immunoprecipitation), and this interaction induces mitochondrial dysfunction (membrane potential depolarization, increased ROS), elevated Bax/Bcl-2 ratio, and Caspase-3 activation to promote anoikis; PI3K activator 740Y-P reversed these effects.","method":"CAMK1 overexpression in CRC cell lines, co-immunoprecipitation of CAMK1 with PI3K, phosphorylation assays, mitochondrial membrane potential (JC-1), ROS measurement, apoptosis assays, mouse tumor and metastasis models, rescue with PI3K activator","journal":"FASEB journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — co-IP for interaction, in vivo mouse model, pharmacological rescue, multiple orthogonal readouts, single lab","pmids":["42175534"],"is_preprint":false},{"year":2024,"finding":"IGF2BP3 promotes stability of CAMK1 mRNA through m6A modification, increasing CAMK1 protein levels; CAMK1 inhibits mitochondrial fission, and conditional knockout of CAMK1 in proximal tubules aggravates kidney injury and promotes mitochondrial fission in diabetic mice.","method":"Proximal tubule-specific CAMK1 knockout mice, STZ-induced diabetes model, RIP assay, dual-luciferase reporter assay, MeRIP (m6A), actinomycin D mRNA stability assay, electron microscopy of mitochondria, JC-1 staining","journal":"Biochimica et biophysica acta. Molecular basis of disease","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — tissue-specific KO with defined phenotype, multiple orthogonal methods for mRNA stability, single lab","pmids":["38216068"],"is_preprint":false}],"current_model":"CAMK1 (CaMKIα) is a Ca2+/calmodulin-dependent serine/threonine kinase whose activity is governed by an autoinhibitory segment that sequesters the activation-loop Thr177 and occludes the substrate-binding site; binding of Ca2+/CaM relieves autoinhibition, and upstream CaMKK phosphorylates Thr177 to fully activate the enzyme. Once active, CAMK1 phosphorylates diverse substrates including GCM1 (Ser47) to promote SENP1-dependent desumoylation, HDAC5 (Ser259/Ser498) to drive nuclear export and de-repress transcription, PINK1 (Ser228) to activate mitophagy, and nuclear CaMKP-N (Ser480) to provide negative feedback on CaMK signaling; through binding Ca2+/CaM and importin IMA-3, CaMKI also translocates to the nucleus to regulate gene transcription and behavioral plasticity."},"narrative":{"mechanistic_narrative":"CAMK1 (CaMKIα) is a Ca2+/calmodulin-dependent serine/threonine kinase that couples intracellular calcium signals to transcriptional, organelle, and behavioral outputs [PMID:21791615, PMID:34766550]. Its activity is gated by an autoinhibitory mechanism: crystal structures show that in the autoinhibited state an activation segment adopts a helical conformation that, together with the autoinhibitory segment, constrains the αC/αD helices, sequesters Thr177 from phosphorylation, and occludes the substrate-binding site, whereas ATP binding dissociates the regulatory region from the catalytic core to yield an active conformation [PMID:23028635]; deletion of the autoinhibitory domain produces constitutively active, Ca2+-independent kinase with broad substrate specificity [PMID:27207832]. Once activated, CAMK1 phosphorylates substrates to control gene expression and cell fusion: downstream of cAMP/Epac1/Rap1 it phosphorylates GCM1 at Ser47 to promote SENP1-dependent desumoylation and activation of GCM1, and it phosphorylates HDAC5 at Ser259/Ser498 to drive nuclear export and de-repress GCM1-driven syncytin-1/2 expression and trophoblast fusion [PMID:21791615, PMID:23867755]. CAMK1 also activates the nuclear phosphatase CaMKP-N/PPM1E by phosphorylating Ser480, providing negative feedback on multifunctional CaMK signaling [PMID:22627141], and phosphorylates PINK1 at Ser228 to recruit Parkin and activate mitophagy [PMID:35145192]. It contributes to starvation-induced autophagosome formation through WIPI-1 puncta downstream of Ca2+/CaMKK [PMID:21896713] and to granulocyte effector functions including phagocytosis, ROS production, migration, and adhesion [PMID:15840691]. In C. elegans, the CaMKI ortholog CMK-1 undergoes Ca2+/CaM-driven, IMA-3 importin-dependent nuclear translocation that underlies experience-dependent gene transcription and behavioral plasticity across thermosensory, chemosensory, and developmental decisions [PMID:34766550, PMID:26335407]. CAMK1 has been linked to mitochondrial homeostasis and disease in mammalian tissues, restraining mitochondrial fission to protect against diabetic kidney injury [PMID:38216068] and, when overexpressed, suppressing PI3K/AKT signaling to drive mitochondrial dysfunction and anoikis in colorectal cancer cells [PMID:42175534].","teleology":[{"year":2005,"claim":"Established that a granulocyte-restricted CaMKI-like kinase translates chemoattractant-induced calcium rises into neutrophil effector functions, linking the kinase to innate immune cell behavior.","evidence":"Peptide inhibitor and functional assays (phagocytosis, ROS, migration, adhesion) in primary human granulocytes","pmids":["15840691"],"confidence":"Medium","gaps":["No direct substrate phosphorylated by CKLiK identified","Reliance on a single peptide inhibitor rather than genetic loss-of-function"]},{"year":2008,"claim":"Implicated CaMKI in cAMP-driven transcription by linking it to Nur77 promoter activity, an early hint at a transcriptional regulatory role.","evidence":"Promoter-reporter assays with pharmacological CaMK inhibition in MA-10 Leydig cells","pmids":["18835829"],"confidence":"Low","gaps":["Pharmacological inhibition only — no direct CaMKI substrate or knockdown","Cannot distinguish CaMKI from other CaMK family members"]},{"year":2011,"claim":"Defined a direct CAMK1 substrate by showing the cAMP/Epac1/Rap1 cascade activates CaMKI to phosphorylate GCM1 Ser47, establishing CAMK1 as a regulator of trophoblast fusion through control of SUMO-dependent transcription factor activity.","evidence":"RNAi, phosphomimetic GCM1 mutants, reciprocal co-IP in BeWo placental cells","pmids":["21791615"],"confidence":"High","gaps":["Mechanism of how Ser47 phosphorylation enhances SENP1 recruitment not structurally resolved","Direct kinase-substrate phosphorylation shown largely in cells"]},{"year":2011,"claim":"Distinguished CaMKI from CaMKIV as the calcium-dependent kinase required for early autophagosome membrane formation, placing CAMK1 in starvation-induced autophagy downstream of CaMKK and independent of AMPK.","evidence":"siRNA knockdown, WIPI-1 puncta high-throughput analysis, LC3 lipidation, pharmacological inhibitors","pmids":["21896713"],"confidence":"Medium","gaps":["No CAMK1 substrate in the autophagy machinery identified","Single lab, single cellular system"]},{"year":2012,"claim":"Resolved the structural basis of CAMK1 autoinhibition and activation, explaining how the activation segment and autoinhibitory segment sequester Thr177 and block substrate binding until ATP/regulatory dissociation.","evidence":"X-ray crystallography of apo and ATP-bound CaMKIα truncates","pmids":["23028635"],"confidence":"High","gaps":["Structures do not capture the Ca2+/CaM-bound activation intermediate","CaMKK-phosphorylated active full-length state not crystallized"]},{"year":2012,"claim":"Identified a negative-feedback substrate, showing CaMKI phosphorylates nuclear CaMKP-N/PPM1E at Ser480 to enhance phosphatase activity and dampen multifunctional CaMK signaling.","evidence":"In vitro kinase assay, S480A/D/E mutagenesis, phosphatase assays, Neuro2a cell transfection","pmids":["22627141"],"confidence":"High","gaps":["Physiological context of CaMKP-N feedback in mammalian neurons not established","Demonstrated in vitro and in heterologous cells"]},{"year":2013,"claim":"Extended the Epac1/Rap1/CaMKI pathway by showing CaMKI phosphorylates HDAC5 at Ser259/Ser498 to drive its nuclear export, linking the kinase to chromatin de-repression and syncytin-1 expression.","evidence":"Phospho-specific antibodies, reciprocal co-IP, constitutively active Epac1/CaMKI, RNAi, immunofluorescence","pmids":["23867755"],"confidence":"High","gaps":["Direct versus indirect phosphorylation of HDAC5 by CaMKI not fully separated from pathway effects","Restricted to placental cell model"]},{"year":2015,"claim":"Defined isoform-specific regulation, showing CaMKIδ is phosphatase-resistant via N-terminal residues, allowing a Ca2+-independent 'primed' active state that phosphorylates CREB.","evidence":"In vitro dephosphorylation assays, chimeric/point mutants, CREB phosphorylation assays in 293T cells","pmids":["25994484"],"confidence":"High","gaps":["Physiological consequences of constitutive CaMKIδ activity in vivo unclear","Specific to the δ isoform, not CaMKIα"]},{"year":2015,"claim":"Demonstrated cell-type-specific and feeding-state-dependent CaMKI signaling, with CMK-1 controlling daf-7 TGF-β and daf-28 insulin-like peptide expression to govern the dauer developmental decision.","evidence":"C. elegans genetics, cell-specific rescue, transcriptional reporters, live subcellular imaging","pmids":["26335407"],"confidence":"High","gaps":["Direct nuclear substrates linking CMK-1 to daf-7/daf-28 transcription not identified","Ortholog-based; mammalian relevance inferred"]},{"year":2016,"claim":"Confirmed by reconstitution that the autoinhibitory domain suppresses basal activity, since an autoinhibitory-domain-deleted CaMKIδ fragment is constitutively active with broad substrate specificity.","evidence":"Recombinant E. coli expression, in vitro kinase and substrate specificity assays","pmids":["27207832"],"confidence":"Medium","gaps":["Broad in vitro specificity may not reflect cellular substrate selectivity","Single study, zebrafish ortholog"]},{"year":2018,"claim":"Placed CMK-1 downstream of sensory calcium signals in chemosensory learning, showing it is required in ASE neurons for salt-aversive behavioral plasticity.","evidence":"C. elegans cmk-1 loss-of-function, microfluidic calcium imaging, behavioral assays","pmids":["29875264"],"confidence":"Medium","gaps":["Molecular substrates mediating the learning phenotype not identified","Effects on sensory calcium responses described as subtle"]},{"year":2021,"claim":"Established the mechanism of calcium-triggered CAMK1 nuclear translocation, showing Ca2+/CaM binding increases CMK-1 affinity for IMA-3 importin to drive slow nuclear import matched to sensory adaptation timescales.","evidence":"In vivo live imaging, optogenetic Ca2+ control, genetic manipulation, co-IP of CMK-1 with IMA-3","pmids":["34766550"],"confidence":"High","gaps":["Nuclear targets driving behavioral plasticity not enumerated","Conservation of the IMA-3/importin interaction in mammals not tested here"]},{"year":2022,"claim":"Connected CAMK1 to mitophagy, showing pitavastatin-driven mitochondrial calcium release activates CAMK1 (Thr177), which phosphorylates PINK1 Ser228 to recruit Parkin and activate mitophagy in endothelial progenitor cells.","evidence":"Phospho-CAMK1/PINK1 Western blots, PINK1-KO mice, Atg7 silencing, calcium measurements, pharmacology","pmids":["35145192"],"confidence":"Medium","gaps":["Direct CAMK1-PINK1 phosphorylation not reconstituted in vitro","Single lab, single cell type"]},{"year":2024,"claim":"Linked CAMK1 to mitochondrial dynamics in cancer, showing CAMK1 overexpression interacts with PI3K, suppresses PI3K/AKT signaling, and induces mitochondrial dysfunction and anoikis in colorectal cancer.","evidence":"Overexpression, co-IP with PI3K, JC-1/ROS/apoptosis assays, mouse tumor models, PI3K-activator rescue","pmids":["42175534"],"confidence":"Medium","gaps":["Whether CAMK1 directly phosphorylates PI3K unresolved","Overexpression context may not reflect endogenous CAMK1 levels"]},{"year":2024,"claim":"Identified CAMK1 as a regulator of mitochondrial fission and renal protection, with IGF2BP3/m6A stabilizing CAMK1 mRNA and proximal-tubule CAMK1 knockout worsening diabetic kidney injury.","evidence":"Proximal-tubule CAMK1 knockout mice, STZ diabetes, RIP/MeRIP/luciferase, mRNA stability assay, EM of mitochondria","pmids":["38216068"],"confidence":"Medium","gaps":["Direct fission-machinery substrate of CAMK1 not identified","Mechanism connecting kinase activity to fission control unresolved"]},{"year":2025,"claim":"Began systematic substrate mapping, identifying hundreds of CMK-1 phosphotargets including calcineurin TAX-6, and revealing antagonistic CMK-1/calcineurin control of thermal nociception and adaptation.","evidence":"In vitro kinase assays with MS phosphoproteomics, C. elegans genetics, cell-specific manipulation","pmids":["40305390"],"confidence":"Medium","gaps":["Direct TAX-6 phosphorylation may not underlie the behavioral phenotype","Most identified substrates not individually validated"]},{"year":null,"claim":"How CAMK1's distinct outputs — transcriptional control, mitophagy/mitochondrial dynamics, autophagy, and immune effector functions — are selected by upstream calcium-source and isoform context in mammalian cells remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No unified substrate-selection logic across tissues established","Mammalian nuclear translocation mechanism not directly demonstrated","Few direct substrates validated in mammalian systems beyond GCM1, HDAC5, CaMKP-N, and PINK1"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0140096","term_label":"catalytic activity, acting on a protein","supporting_discovery_ids":[2,3,4,6,10,13]},{"term_id":"GO:0016740","term_label":"transferase activity","supporting_discovery_ids":[0,2,3,4,6,13]},{"term_id":"GO:0140657","term_label":"ATP-dependent activity","supporting_discovery_ids":[0]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[4]}],"localization":[{"term_id":"GO:0005634","term_label":"nucleus","supporting_discovery_ids":[7,8]},{"term_id":"GO:0005829","term_label":"cytosol","supporting_discovery_ids":[7]}],"pathway":[{"term_id":"R-HSA-74160","term_label":"Gene expression (Transcription)","supporting_discovery_ids":[2,3]},{"term_id":"R-HSA-9612973","term_label":"Autophagy","supporting_discovery_ids":[1,6]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[2,3,6,14]},{"term_id":"R-HSA-1266738","term_label":"Developmental Biology","supporting_discovery_ids":[2,8]}],"complexes":[],"partners":["GCM1","HDAC5","PPM1E","PINK1","PI3K","IMA-3","TAX-6"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q14012","full_name":"Calcium/calmodulin-dependent protein kinase type 1","aliases":["CaM kinase I","CaM-KI","CaM kinase I alpha","CaMKI-alpha"],"length_aa":370,"mass_kda":41.3,"function":"Calcium/calmodulin-dependent protein kinase that operates in the calcium-triggered CaMKK-CaMK1 signaling cascade and, upon calcium influx, regulates transcription activators activity, cell cycle, hormone production, cell differentiation, actin filament organization and neurite outgrowth. Recognizes the substrate consensus sequence [MVLIF]-x-R-x(2)-[ST]-x(3)-[MVLIF]. Regulates axonal extension and growth cone motility in hippocampal and cerebellar nerve cells. Upon NMDA receptor-mediated Ca(2+) elevation, promotes dendritic growth in hippocampal neurons and is essential in synapses for full long-term potentiation (LTP) and ERK2-dependent translational activation. Downstream of NMDA receptors, promotes the formation of spines and synapses in hippocampal neurons by phosphorylating ARHGEF7/BETAPIX on 'Ser-694', which results in the enhancement of ARHGEF7 activity and activation of RAC1. Promotes neuronal differentiation and neurite outgrowth by activation and phosphorylation of MARK2 on 'Ser-91', 'Ser-92', 'Ser-93' and 'Ser-294'. Promotes nuclear export of HDAC5 and binding to 14-3-3 by phosphorylation of 'Ser-259' and 'Ser-498' in the regulation of muscle cell differentiation. Regulates NUMB-mediated endocytosis by phosphorylation of NUMB on 'Ser-276' and 'Ser-295'. Involved in the regulation of basal and estrogen-stimulated migration of medulloblastoma cells through ARHGEF7/BETAPIX phosphorylation (By similarity). Is required for proper activation of cyclin-D1/CDK4 complex during G1 progression in diploid fibroblasts. Plays a role in K(+) and ANG2-mediated regulation of the aldosterone synthase (CYP11B2) to produce aldosterone in the adrenal cortex. Phosphorylates EIF4G3/eIF4GII. In vitro phosphorylates CREB1, ATF1, CFTR, MYL9 and SYN1/synapsin I","subcellular_location":"Cytoplasm; Nucleus","url":"https://www.uniprot.org/uniprotkb/Q14012/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/CAMK1","classification":"Not Classified","n_dependent_lines":0,"n_total_lines":1208,"dependency_fraction":0.0},"opencell":{"profiled":true,"resolved_as":"","ensg_id":"ENSG00000134072","cell_line_id":"CID001137","localizations":[{"compartment":"cytoplasmic","grade":3},{"compartment":"nucleoplasm","grade":1}],"interactors":[{"gene":"CALM2;CALM3;CALM1","stoichiometry":10.0},{"gene":"CALM1","stoichiometry":0.2},{"gene":"NUMA1","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/target/CID001137","total_profiled":1310},"omim":[{"mim_id":"615002","title":"CALCIUM/CALMODULIN-DEPENDENT PROTEIN KINASE KINASE 2, BETA; CAMKK2","url":"https://www.omim.org/entry/615002"},{"mim_id":"611411","title":"CALCIUM/CALMODULIN-DEPENDENT PROTEIN KINASE KINASE 1, ALPHA; CAMKK1","url":"https://www.omim.org/entry/611411"},{"mim_id":"607957","title":"CALCIUM/CALMODULIN-DEPENDENT PROTEIN KINASE I-DELTA; CAMK1D","url":"https://www.omim.org/entry/607957"},{"mim_id":"607670","title":"SERINE/THREONINE PROTEIN KINASE 33; STK33","url":"https://www.omim.org/entry/607670"},{"mim_id":"605488","title":"cAMP-REGULATED PHOSPHOPROTEIN 21; ARPP21","url":"https://www.omim.org/entry/605488"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Cytosol","reliability":"Approved"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in all","driving_tissues":[{"tissue":"adrenal gland","ntpm":99.5}],"url":"https://www.proteinatlas.org/search/CAMK1"},"hgnc":{"alias_symbol":["CaMKI","CaMKI-alpha"],"prev_symbol":[]},"alphafold":{"accession":"Q14012","domains":[{"cath_id":"3.30.200.20","chopping":"11-97","consensus_level":"high","plddt":85.7559,"start":11,"end":97},{"cath_id":"1.10.510.10","chopping":"100-301","consensus_level":"high","plddt":88.6208,"start":100,"end":301}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q14012","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q14012-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q14012-F1-predicted_aligned_error_v6.png","plddt_mean":78.38},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=CAMK1","jax_strain_url":"https://www.jax.org/strain/search?query=CAMK1"},"sequence":{"accession":"Q14012","fasta_url":"https://rest.uniprot.org/uniprotkb/Q14012.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q14012/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q14012"}},"corpus_meta":[{"pmid":"21896713","id":"PMC_21896713","title":"Ca2+/calmodulin-dependent kinase (CaMK) signaling via CaMKI and AMP-activated protein kinase contributes to the regulation of WIPI-1 at the onset of autophagy.","date":"2011","source":"Molecular pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/21896713","citation_count":71,"is_preprint":false},{"pmid":"21791615","id":"PMC_21791615","title":"A novel cyclic AMP/Epac1/CaMKI signaling cascade promotes GCM1 desumoylation and placental cell fusion.","date":"2011","source":"Molecular and cellular biology","url":"https://pubmed.ncbi.nlm.nih.gov/21791615","citation_count":44,"is_preprint":false},{"pmid":"15840691","id":"PMC_15840691","title":"Characterization of the role of CaMKI-like kinase (CKLiK) in human granulocyte function.","date":"2005","source":"Blood","url":"https://pubmed.ncbi.nlm.nih.gov/15840691","citation_count":43,"is_preprint":false},{"pmid":"18835829","id":"PMC_18835829","title":"cAMP-induced expression of the orphan nuclear receptor Nur77 in MA-10 Leydig cells involves a CaMKI pathway.","date":"2008","source":"Journal of andrology","url":"https://pubmed.ncbi.nlm.nih.gov/18835829","citation_count":42,"is_preprint":false},{"pmid":"33342045","id":"PMC_33342045","title":"Expression of CAMK1 and its association with clinicopathologic characteristics in pancreatic cancer.","date":"2020","source":"Journal of cellular and molecular medicine","url":"https://pubmed.ncbi.nlm.nih.gov/33342045","citation_count":36,"is_preprint":false},{"pmid":"26335407","id":"PMC_26335407","title":"Feeding state-dependent regulation of developmental plasticity via CaMKI and neuroendocrine signaling.","date":"2015","source":"eLife","url":"https://pubmed.ncbi.nlm.nih.gov/26335407","citation_count":32,"is_preprint":false},{"pmid":"25613640","id":"PMC_25613640","title":"Capsicum annuum transcription factor WRKYa positively regulates defense response upon TMV infection and is a substrate of CaMK1 and CaMK2.","date":"2015","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/25613640","citation_count":30,"is_preprint":false},{"pmid":"35145192","id":"PMC_35145192","title":"Pitavastatin activates mitophagy to protect EPC proliferation through a calcium-dependent CAMK1-PINK1 pathway in atherosclerotic mice.","date":"2022","source":"Communications biology","url":"https://pubmed.ncbi.nlm.nih.gov/35145192","citation_count":26,"is_preprint":false},{"pmid":"29875264","id":"PMC_29875264","title":"Loss of CaMKI Function Disrupts Salt Aversive Learning in C. elegans.","date":"2018","source":"The Journal of neuroscience : the official journal of the Society for Neuroscience","url":"https://pubmed.ncbi.nlm.nih.gov/29875264","citation_count":26,"is_preprint":false},{"pmid":"33238205","id":"PMC_33238205","title":"Exosomal miR-211 contributes to pulmonary hypertension via attenuating CaMK1/PPAR-γaxis.","date":"2020","source":"Vascular pharmacology","url":"https://pubmed.ncbi.nlm.nih.gov/33238205","citation_count":25,"is_preprint":false},{"pmid":"23867755","id":"PMC_23867755","title":"Involvement of Epac1/Rap1/CaMKI/HDAC5 signaling cascade in the regulation of placental cell fusion.","date":"2013","source":"Molecular human reproduction","url":"https://pubmed.ncbi.nlm.nih.gov/23867755","citation_count":23,"is_preprint":false},{"pmid":"24825433","id":"PMC_24825433","title":"CAMK1 phosphoinositide signal-mediated protein sorting and transport network in human hepatocellular carcinoma (HCC) by biocomputation.","date":"2014","source":"Cell biochemistry and biophysics","url":"https://pubmed.ncbi.nlm.nih.gov/24825433","citation_count":17,"is_preprint":false},{"pmid":"34766550","id":"PMC_34766550","title":"Ca2+/CaM binding to CaMKI promotes IMA-3 importin binding and nuclear translocation in sensory neurons to control behavioral adaptation.","date":"2021","source":"eLife","url":"https://pubmed.ncbi.nlm.nih.gov/34766550","citation_count":16,"is_preprint":false},{"pmid":"38216068","id":"PMC_38216068","title":"IGF2BP3-stabilized CAMK1 regulates the mitochondrial dynamics of renal tubule to alleviate diabetic nephropathy.","date":"2024","source":"Biochimica et biophysica acta. Molecular basis of disease","url":"https://pubmed.ncbi.nlm.nih.gov/38216068","citation_count":14,"is_preprint":false},{"pmid":"23028635","id":"PMC_23028635","title":"Crystal structures of human CaMKIα reveal insights into the regulation mechanism of CaMKI.","date":"2012","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/23028635","citation_count":12,"is_preprint":false},{"pmid":"30125682","id":"PMC_30125682","title":"1800 MHz radiofrequency fields inhibits testosterone production via CaMKI /RORα pathway.","date":"2018","source":"Reproductive toxicology (Elmsford, N.Y.)","url":"https://pubmed.ncbi.nlm.nih.gov/30125682","citation_count":11,"is_preprint":false},{"pmid":"35887424","id":"PMC_35887424","title":"Characterization and Functional Analysis of a New Calcium/Calmodulin-Dependent Protein Kinase (CaMK1) in the Citrus Pathogenic Fungus Penicillium italicum.","date":"2022","source":"Journal of fungi (Basel, Switzerland)","url":"https://pubmed.ncbi.nlm.nih.gov/35887424","citation_count":10,"is_preprint":false},{"pmid":"22627141","id":"PMC_22627141","title":"Phosphorylation and activation of nuclear Ca2+/calmodulin-dependent protein kinase phosphatase (CaMKP-N/PPM1E) by Ca2+/calmodulin-dependent protein kinase I (CaMKI).","date":"2012","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/22627141","citation_count":10,"is_preprint":false},{"pmid":"25081204","id":"PMC_25081204","title":"Negative feedback regulation of calcineurin-dependent Prz1 transcription factor by the CaMKK-CaMK1 axis in fission yeast.","date":"2014","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/25081204","citation_count":10,"is_preprint":false},{"pmid":"25994484","id":"PMC_25994484","title":"The Phosphatase-Resistant Isoform of CaMKI, Ca²⁺/Calmodulin-Dependent Protein Kinase Iδ (CaMKIδ), Remains in Its \"Primed\" Form without Ca²⁺ Stimulation.","date":"2015","source":"Biochemistry","url":"https://pubmed.ncbi.nlm.nih.gov/25994484","citation_count":9,"is_preprint":false},{"pmid":"27207832","id":"PMC_27207832","title":"High-performance CaMKI: A highly active and stable form of CaMKIδ produced by high-level soluble expression in Escherichia coli.","date":"2016","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/27207832","citation_count":5,"is_preprint":false},{"pmid":"40305390","id":"PMC_40305390","title":"Antagonist actions of CMK-1/CaMKI and TAX-6/calcineurin along the C. elegans thermal avoidance circuit orchestrate adaptation of nociceptive response to repeated stimuli.","date":"2025","source":"eLife","url":"https://pubmed.ncbi.nlm.nih.gov/40305390","citation_count":3,"is_preprint":false},{"pmid":"42175534","id":"PMC_42175534","title":"CAMK1 Suppresses Anoikis Resistance and Liver Metastasis in Colorectal Cancer.","date":"2026","source":"FASEB journal : official publication of the Federation of American Societies for Experimental Biology","url":"https://pubmed.ncbi.nlm.nih.gov/42175534","citation_count":0,"is_preprint":false},{"pmid":"41007373","id":"PMC_41007373","title":"Dysregulation of Protein Kinase CaMKI Leads to Autism-Related Phenotypes in Synaptic Connectivity, Sleep, Sociality, and Aging-Dependent Degeneration in Drosophila.","date":"2025","source":"Biology","url":"https://pubmed.ncbi.nlm.nih.gov/41007373","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":16023,"output_tokens":4550,"usd":0.05816,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":12602,"output_tokens":5409,"usd":0.099117,"stage2_stop_reason":"end_turn"},"total_usd":0.157277,"stage1_batch_id":"msgbatch_01ACAxJQabDsht39JXeWG22d","stage2_batch_id":"msgbatch_01QEU22A9U5sbPTgsMzTmvSf","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2012,\n      \"finding\": \"Crystal structures of human CaMKIα (apo form and ATP-bound complexes) revealed that in the autoinhibited state, the activation segment adopts a helical conformation that together with the autoinhibitory segment constrains helices αC and αD in inactive conformations, sequesters Thr177 from phosphorylation, and occludes the substrate-binding site. In an ATP-bound active structure, the regulatory region is dissociated from the catalytic core and the catalytic site assumes an active conformation.\",\n      \"method\": \"X-ray crystallography of four structures of three CaMKIα truncates in apo and ATP-bound forms\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — multiple crystal structures with functional interpretation, multiple orthogonal structural states analyzed in one study\",\n      \"pmids\": [\"23028635\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"CaMKI (but not CaMKIV) contributes to stimulation of WIPI-1 puncta formation at the onset of autophagy downstream of Ca2+/CaMKK signaling; siRNA-mediated knockdown of CaMKI reduced starvation-induced autophagosomal membrane formation independently of AMPKα1/α2.\",\n      \"method\": \"siRNA knockdown of CaMKI, automated high-throughput WIPI-1 puncta analysis, LC3 lipidation assays, pharmacological inhibitors (STO-609, KN-93)\",\n      \"journal\": \"Molecular pharmacology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean siRNA knockdown with defined cellular phenotype, multiple pharmacological controls, single lab\",\n      \"pmids\": [\"21896713\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Epac1 and Rap1, in response to cAMP, activate CaMKI to phosphorylate Ser47 of GCM1; this phosphorylation facilitates interaction between GCM1 and the desumoylating enzyme SENP1, leading to GCM1 desumoylation and activation, thereby promoting syncytin-1/2 expression and trophoblast cell fusion.\",\n      \"method\": \"RNAi knockdown, phosphomimetic/non-phosphorylatable GCM1 mutants, co-immunoprecipitation, transient expression assays in BeWo placental cells\",\n      \"journal\": \"Molecular and cellular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal co-IP, phosphomimetic mutagenesis (S47D), RNAi rescue experiments, multiple orthogonal methods in one study\",\n      \"pmids\": [\"21791615\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"The Epac1/Rap1/CaMKI signaling cascade phosphorylates HDAC5 on Ser259 and Ser498 in a Rap1- and CaMKI-dependent manner, causing nuclear export of HDAC5, thereby relieving HDAC5-mediated deacetylation and transcriptional repression of GCM1 and promoting syncytin-1 expression and placental cell fusion.\",\n      \"method\": \"Co-immunoprecipitation, immunofluorescence microscopy, phospho-specific antibodies against HDAC5, transient expression of constitutively active Epac1 and CaMKI, RNAi\",\n      \"journal\": \"Molecular human reproduction\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP, phospho-specific antibodies, constitutively active constructs, RNAi, multiple orthogonal methods, replicates the Epac1/CaMKI pathway from PMID:21791615\",\n      \"pmids\": [\"23867755\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"CaMKI phosphorylates nuclear CaMK phosphatase (CaMKP-N/PPM1E; zebrafish ortholog zCaMKP-N) at Ser-480 in vitro; phosphorylation-mimic mutants (S480D/S480E) showed higher phosphatase activity and more potently attenuated CaMKII autophosphorylation in cells, indicating CaMKI activates CaMKP-N to provide negative feedback on multifunctional CaMKs.\",\n      \"method\": \"In vitro kinase assay with activated CaMKI, site-directed mutagenesis (S480A, S480D, S480E), solution-based phosphatase assay, co-transfection in Neuro2a cells with ionomycin treatment\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro kinase assay with mutagenesis, confirmed in cell-based assay, single lab but multiple orthogonal methods\",\n      \"pmids\": [\"22627141\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"CaMKIδ isoform is phosphatase-resistant compared to CaMKIα due to its N-terminal region structure (residues Pro-57, Lys-62, Ser-66, Ile-68, and Arg-76); CaMKP/PPM1F barely dephosphorylates CaMKIδ, allowing it to remain in a 'primed' phosphorylated, active state under low-Ca2+ conditions and to phosphorylate CREB without Ca2+ stimulation.\",\n      \"method\": \"Transient expression in 293T cells, in vitro dephosphorylation assay with CaMKP/PPM1F, chimeric and point mutants of CaMKIδ and CaMKIα, CREB phosphorylation assay\",\n      \"journal\": \"Biochemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro enzymatic assay with systematic mutagenesis identifying causative residues, confirmed in cellular system, single lab\",\n      \"pmids\": [\"25994484\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Pitavastatin promotes mitochondrial calcium release into the cytoplasm, which phosphorylates CAMK1 (at Thr177); phosphorylated CAMK1 in turn phosphorylates PINK1 at Ser228, which recruits PARK2 (Parkin) and phosphorylates its Ser65 to activate mitophagy, improving endothelial progenitor cell proliferation.\",\n      \"method\": \"CAMK1 phosphorylation assays in EPCs, PINK1-KO mice, Atg7 silencing, intracellular calcium measurements, Western blot for phospho-CAMK1 (Thr177) and phospho-PINK1 (Ser228), pharmacological inhibition\",\n      \"journal\": \"Communications biology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — defined phosphorylation cascade with specific residues, genetic KO validation, single lab\",\n      \"pmids\": [\"35145192\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"In C. elegans thermosensory neurons, elevation of intracellular Ca2+ is necessary and sufficient for CMK-1 (CaMKI ortholog) nuclear import; Ca2+/CaM binding to CMK-1 increases its affinity for IMA-3 importin, driving nuclear translocation with slow kinetics that matches the timescale of sensory adaptation and is essential for experience-dependent behavioral plasticity and gene transcription control.\",\n      \"method\": \"In vivo live imaging in C. elegans, genetic manipulation (loss-of-function, constitutively active CMK-1), optogenetics to control Ca2+, co-immunoprecipitation of CMK-1 with IMA-3 importin\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP, in vivo live imaging, multiple genetic manipulations, optogenetic control, functional behavioral readouts in a single rigorous study\",\n      \"pmids\": [\"34766550\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"CMK-1 (CaMKI ortholog in C. elegans) regulates the dauer developmental decision as a function of feeding state; CMK-1 acts cell-autonomously in ASI neurons to regulate daf-7 TGF-β expression and non-cell-autonomously in AWC neurons to regulate daf-28 insulin-like peptide expression; food availability dynamically regulates subcellular localization of CMK-1 in AWC neurons.\",\n      \"method\": \"C. elegans genetics (cmk-1 mutants), cell-specific rescue experiments, transgenic reporters for daf-7 and daf-28, live imaging of CMK-1 subcellular localization\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — cell-autonomous vs non-cell-autonomous genetic dissection, live subcellular localization, multiple neuronal circuit-level rescue experiments\",\n      \"pmids\": [\"26335407\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"CMK-1 (CaMKI ortholog) is required in ASE chemosensory neurons for salt-aversive learning in C. elegans; loss of cmk-1 has subtle effects on sensory-evoked calcium responses in ASE axons and their modulation by salt conditioning, placing CMK-1 as a regulator of behavioral plasticity downstream of sensory calcium signals.\",\n      \"method\": \"C. elegans genetics (cmk-1 loss-of-function), microfluidics-based calcium imaging in ASE neurons, behavioral assays\",\n      \"journal\": \"The Journal of neuroscience\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — clean genetic loss-of-function with defined behavioral phenotype and calcium imaging, single lab\",\n      \"pmids\": [\"29875264\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"In C. elegans, CMK-1 (CaMKI ortholog) and calcineurin TAX-6 have antagonistic roles in modulating thermal nociception and adaptation to repeated stimuli; in vitro kinase assay combined with phosphoproteomics identified hundreds of CMK-1 substrates including the calcineurin A subunit TAX-6 (phosphorylated in its conserved regulatory domain); cell-specific analysis placed CMK-1 in AFD and ASER neurons and TAX-6 in FLP neurons and interneurons.\",\n      \"method\": \"In vitro kinase assays, mass-spectrometry-based phosphoproteomics, C. elegans genetics, pharmacological analyses, cell-specific genetic manipulations\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — in vitro kinase assay with MS-based phosphoproteomics for substrate identification, genetic epistasis, but the direct TAX-6 phosphorylation may not underlie the behavioral phenotype as noted in the abstract\",\n      \"pmids\": [\"40305390\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"Ca2+/calmodulin kinase I regulates Nur77 (Nr4a1) promoter activity in MA-10 Leydig cells; cAMP-mediated induction of Nur77 expression involves a CaMK-dependent pathway with distinct regulatory elements for basal and cAMP-induced Nur77 transcription.\",\n      \"method\": \"Promoter-reporter assays, pharmacological CaMK inhibition, transient transfection in MA-10 cells\",\n      \"journal\": \"Journal of andrology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — promoter-reporter assays with pharmacological inhibition only, no direct CaMKI substrate identification or KD\",\n      \"pmids\": [\"18835829\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"CKLiK (CaMKI-like kinase restricted to granulocytes) activity is induced by fMLP and PAF stimulation in parallel with intracellular Ca2+ rise; inhibition of CKLiK with a cell-permeable peptide inhibitor reduced phagocytosis, fMLP-induced ROS production, neutrophil migration, and β2-integrin-mediated adhesion.\",\n      \"method\": \"CKLiK peptide inhibitor (CKLiK297-321), kinase activity assays, phagocytosis assay, ROS/respiratory burst assay, migration assay, adhesion assay in primary human granulocytes\",\n      \"journal\": \"Blood\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple functional assays with a specific peptide inhibitor in primary human cells, defined cellular phenotypes, single lab\",\n      \"pmids\": [\"15840691\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"A constitutively active fragment of zebrafish CaMKIδ (zCaMKIδ(1-299)) lacking the autoinhibitory domain showed high, Ca2+-independent kinase activity comparable to CaMKK-activated wild-type CaMKIδ, confirming that the autoinhibitory domain suppresses basal kinase activity; the fragment exhibited broad substrate specificity similar to full-length activated CaMKIδ.\",\n      \"method\": \"Recombinant protein expression in E. coli, in vitro kinase activity assays, substrate specificity profiling, comparison with PKAc and CaMKII\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Weak — in vitro reconstitution with deletion mutant confirming autoinhibitory mechanism, single lab, single study\",\n      \"pmids\": [\"27207832\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"CAMK1 overexpression in colorectal cancer cells inhibits PI3K phosphorylation and downstream AKT pathway activation; CAMK1 interacts with PI3K (by co-immunoprecipitation), and this interaction induces mitochondrial dysfunction (membrane potential depolarization, increased ROS), elevated Bax/Bcl-2 ratio, and Caspase-3 activation to promote anoikis; PI3K activator 740Y-P reversed these effects.\",\n      \"method\": \"CAMK1 overexpression in CRC cell lines, co-immunoprecipitation of CAMK1 with PI3K, phosphorylation assays, mitochondrial membrane potential (JC-1), ROS measurement, apoptosis assays, mouse tumor and metastasis models, rescue with PI3K activator\",\n      \"journal\": \"FASEB journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP for interaction, in vivo mouse model, pharmacological rescue, multiple orthogonal readouts, single lab\",\n      \"pmids\": [\"42175534\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"IGF2BP3 promotes stability of CAMK1 mRNA through m6A modification, increasing CAMK1 protein levels; CAMK1 inhibits mitochondrial fission, and conditional knockout of CAMK1 in proximal tubules aggravates kidney injury and promotes mitochondrial fission in diabetic mice.\",\n      \"method\": \"Proximal tubule-specific CAMK1 knockout mice, STZ-induced diabetes model, RIP assay, dual-luciferase reporter assay, MeRIP (m6A), actinomycin D mRNA stability assay, electron microscopy of mitochondria, JC-1 staining\",\n      \"journal\": \"Biochimica et biophysica acta. Molecular basis of disease\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — tissue-specific KO with defined phenotype, multiple orthogonal methods for mRNA stability, single lab\",\n      \"pmids\": [\"38216068\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"CAMK1 (CaMKIα) is a Ca2+/calmodulin-dependent serine/threonine kinase whose activity is governed by an autoinhibitory segment that sequesters the activation-loop Thr177 and occludes the substrate-binding site; binding of Ca2+/CaM relieves autoinhibition, and upstream CaMKK phosphorylates Thr177 to fully activate the enzyme. Once active, CAMK1 phosphorylates diverse substrates including GCM1 (Ser47) to promote SENP1-dependent desumoylation, HDAC5 (Ser259/Ser498) to drive nuclear export and de-repress transcription, PINK1 (Ser228) to activate mitophagy, and nuclear CaMKP-N (Ser480) to provide negative feedback on CaMK signaling; through binding Ca2+/CaM and importin IMA-3, CaMKI also translocates to the nucleus to regulate gene transcription and behavioral plasticity.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"CAMK1 (CaMKIα) is a Ca2+/calmodulin-dependent serine/threonine kinase that couples intracellular calcium signals to transcriptional, organelle, and behavioral outputs [#2, #7]. Its activity is gated by an autoinhibitory mechanism: crystal structures show that in the autoinhibited state an activation segment adopts a helical conformation that, together with the autoinhibitory segment, constrains the αC/αD helices, sequesters Thr177 from phosphorylation, and occludes the substrate-binding site, whereas ATP binding dissociates the regulatory region from the catalytic core to yield an active conformation [#0]; deletion of the autoinhibitory domain produces constitutively active, Ca2+-independent kinase with broad substrate specificity [#13]. Once activated, CAMK1 phosphorylates substrates to control gene expression and cell fusion: downstream of cAMP/Epac1/Rap1 it phosphorylates GCM1 at Ser47 to promote SENP1-dependent desumoylation and activation of GCM1, and it phosphorylates HDAC5 at Ser259/Ser498 to drive nuclear export and de-repress GCM1-driven syncytin-1/2 expression and trophoblast fusion [#2, #3]. CAMK1 also activates the nuclear phosphatase CaMKP-N/PPM1E by phosphorylating Ser480, providing negative feedback on multifunctional CaMK signaling [#4], and phosphorylates PINK1 at Ser228 to recruit Parkin and activate mitophagy [#6]. It contributes to starvation-induced autophagosome formation through WIPI-1 puncta downstream of Ca2+/CaMKK [#1] and to granulocyte effector functions including phagocytosis, ROS production, migration, and adhesion [#12]. In C. elegans, the CaMKI ortholog CMK-1 undergoes Ca2+/CaM-driven, IMA-3 importin-dependent nuclear translocation that underlies experience-dependent gene transcription and behavioral plasticity across thermosensory, chemosensory, and developmental decisions [#7, #8]. CAMK1 has been linked to mitochondrial homeostasis and disease in mammalian tissues, restraining mitochondrial fission to protect against diabetic kidney injury [#15] and, when overexpressed, suppressing PI3K/AKT signaling to drive mitochondrial dysfunction and anoikis in colorectal cancer cells [#14].\",\n  \"teleology\": [\n    {\n      \"year\": 2005,\n      \"claim\": \"Established that a granulocyte-restricted CaMKI-like kinase translates chemoattractant-induced calcium rises into neutrophil effector functions, linking the kinase to innate immune cell behavior.\",\n      \"evidence\": \"Peptide inhibitor and functional assays (phagocytosis, ROS, migration, adhesion) in primary human granulocytes\",\n      \"pmids\": [\"15840691\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No direct substrate phosphorylated by CKLiK identified\", \"Reliance on a single peptide inhibitor rather than genetic loss-of-function\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Implicated CaMKI in cAMP-driven transcription by linking it to Nur77 promoter activity, an early hint at a transcriptional regulatory role.\",\n      \"evidence\": \"Promoter-reporter assays with pharmacological CaMK inhibition in MA-10 Leydig cells\",\n      \"pmids\": [\"18835829\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Pharmacological inhibition only — no direct CaMKI substrate or knockdown\", \"Cannot distinguish CaMKI from other CaMK family members\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Defined a direct CAMK1 substrate by showing the cAMP/Epac1/Rap1 cascade activates CaMKI to phosphorylate GCM1 Ser47, establishing CAMK1 as a regulator of trophoblast fusion through control of SUMO-dependent transcription factor activity.\",\n      \"evidence\": \"RNAi, phosphomimetic GCM1 mutants, reciprocal co-IP in BeWo placental cells\",\n      \"pmids\": [\"21791615\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism of how Ser47 phosphorylation enhances SENP1 recruitment not structurally resolved\", \"Direct kinase-substrate phosphorylation shown largely in cells\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Distinguished CaMKI from CaMKIV as the calcium-dependent kinase required for early autophagosome membrane formation, placing CAMK1 in starvation-induced autophagy downstream of CaMKK and independent of AMPK.\",\n      \"evidence\": \"siRNA knockdown, WIPI-1 puncta high-throughput analysis, LC3 lipidation, pharmacological inhibitors\",\n      \"pmids\": [\"21896713\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No CAMK1 substrate in the autophagy machinery identified\", \"Single lab, single cellular system\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Resolved the structural basis of CAMK1 autoinhibition and activation, explaining how the activation segment and autoinhibitory segment sequester Thr177 and block substrate binding until ATP/regulatory dissociation.\",\n      \"evidence\": \"X-ray crystallography of apo and ATP-bound CaMKIα truncates\",\n      \"pmids\": [\"23028635\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structures do not capture the Ca2+/CaM-bound activation intermediate\", \"CaMKK-phosphorylated active full-length state not crystallized\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Identified a negative-feedback substrate, showing CaMKI phosphorylates nuclear CaMKP-N/PPM1E at Ser480 to enhance phosphatase activity and dampen multifunctional CaMK signaling.\",\n      \"evidence\": \"In vitro kinase assay, S480A/D/E mutagenesis, phosphatase assays, Neuro2a cell transfection\",\n      \"pmids\": [\"22627141\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological context of CaMKP-N feedback in mammalian neurons not established\", \"Demonstrated in vitro and in heterologous cells\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Extended the Epac1/Rap1/CaMKI pathway by showing CaMKI phosphorylates HDAC5 at Ser259/Ser498 to drive its nuclear export, linking the kinase to chromatin de-repression and syncytin-1 expression.\",\n      \"evidence\": \"Phospho-specific antibodies, reciprocal co-IP, constitutively active Epac1/CaMKI, RNAi, immunofluorescence\",\n      \"pmids\": [\"23867755\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct versus indirect phosphorylation of HDAC5 by CaMKI not fully separated from pathway effects\", \"Restricted to placental cell model\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Defined isoform-specific regulation, showing CaMKIδ is phosphatase-resistant via N-terminal residues, allowing a Ca2+-independent 'primed' active state that phosphorylates CREB.\",\n      \"evidence\": \"In vitro dephosphorylation assays, chimeric/point mutants, CREB phosphorylation assays in 293T cells\",\n      \"pmids\": [\"25994484\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological consequences of constitutive CaMKIδ activity in vivo unclear\", \"Specific to the δ isoform, not CaMKIα\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Demonstrated cell-type-specific and feeding-state-dependent CaMKI signaling, with CMK-1 controlling daf-7 TGF-β and daf-28 insulin-like peptide expression to govern the dauer developmental decision.\",\n      \"evidence\": \"C. elegans genetics, cell-specific rescue, transcriptional reporters, live subcellular imaging\",\n      \"pmids\": [\"26335407\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct nuclear substrates linking CMK-1 to daf-7/daf-28 transcription not identified\", \"Ortholog-based; mammalian relevance inferred\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Confirmed by reconstitution that the autoinhibitory domain suppresses basal activity, since an autoinhibitory-domain-deleted CaMKIδ fragment is constitutively active with broad substrate specificity.\",\n      \"evidence\": \"Recombinant E. coli expression, in vitro kinase and substrate specificity assays\",\n      \"pmids\": [\"27207832\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Broad in vitro specificity may not reflect cellular substrate selectivity\", \"Single study, zebrafish ortholog\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Placed CMK-1 downstream of sensory calcium signals in chemosensory learning, showing it is required in ASE neurons for salt-aversive behavioral plasticity.\",\n      \"evidence\": \"C. elegans cmk-1 loss-of-function, microfluidic calcium imaging, behavioral assays\",\n      \"pmids\": [\"29875264\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular substrates mediating the learning phenotype not identified\", \"Effects on sensory calcium responses described as subtle\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Established the mechanism of calcium-triggered CAMK1 nuclear translocation, showing Ca2+/CaM binding increases CMK-1 affinity for IMA-3 importin to drive slow nuclear import matched to sensory adaptation timescales.\",\n      \"evidence\": \"In vivo live imaging, optogenetic Ca2+ control, genetic manipulation, co-IP of CMK-1 with IMA-3\",\n      \"pmids\": [\"34766550\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Nuclear targets driving behavioral plasticity not enumerated\", \"Conservation of the IMA-3/importin interaction in mammals not tested here\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Connected CAMK1 to mitophagy, showing pitavastatin-driven mitochondrial calcium release activates CAMK1 (Thr177), which phosphorylates PINK1 Ser228 to recruit Parkin and activate mitophagy in endothelial progenitor cells.\",\n      \"evidence\": \"Phospho-CAMK1/PINK1 Western blots, PINK1-KO mice, Atg7 silencing, calcium measurements, pharmacology\",\n      \"pmids\": [\"35145192\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct CAMK1-PINK1 phosphorylation not reconstituted in vitro\", \"Single lab, single cell type\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Linked CAMK1 to mitochondrial dynamics in cancer, showing CAMK1 overexpression interacts with PI3K, suppresses PI3K/AKT signaling, and induces mitochondrial dysfunction and anoikis in colorectal cancer.\",\n      \"evidence\": \"Overexpression, co-IP with PI3K, JC-1/ROS/apoptosis assays, mouse tumor models, PI3K-activator rescue\",\n      \"pmids\": [\"42175534\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether CAMK1 directly phosphorylates PI3K unresolved\", \"Overexpression context may not reflect endogenous CAMK1 levels\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Identified CAMK1 as a regulator of mitochondrial fission and renal protection, with IGF2BP3/m6A stabilizing CAMK1 mRNA and proximal-tubule CAMK1 knockout worsening diabetic kidney injury.\",\n      \"evidence\": \"Proximal-tubule CAMK1 knockout mice, STZ diabetes, RIP/MeRIP/luciferase, mRNA stability assay, EM of mitochondria\",\n      \"pmids\": [\"38216068\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct fission-machinery substrate of CAMK1 not identified\", \"Mechanism connecting kinase activity to fission control unresolved\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Began systematic substrate mapping, identifying hundreds of CMK-1 phosphotargets including calcineurin TAX-6, and revealing antagonistic CMK-1/calcineurin control of thermal nociception and adaptation.\",\n      \"evidence\": \"In vitro kinase assays with MS phosphoproteomics, C. elegans genetics, cell-specific manipulation\",\n      \"pmids\": [\"40305390\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct TAX-6 phosphorylation may not underlie the behavioral phenotype\", \"Most identified substrates not individually validated\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How CAMK1's distinct outputs — transcriptional control, mitophagy/mitochondrial dynamics, autophagy, and immune effector functions — are selected by upstream calcium-source and isoform context in mammalian cells remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No unified substrate-selection logic across tissues established\", \"Mammalian nuclear translocation mechanism not directly demonstrated\", \"Few direct substrates validated in mammalian systems beyond GCM1, HDAC5, CaMKP-N, and PINK1\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0140096\", \"supporting_discovery_ids\": [2, 3, 4, 6, 10, 13]},\n      {\"term_id\": \"GO:0016740\", \"supporting_discovery_ids\": [0, 2, 3, 4, 6, 13]},\n      {\"term_id\": \"GO:0140657\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [4]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005634\", \"supporting_discovery_ids\": [7, 8]},\n      {\"term_id\": \"GO:0005829\", \"supporting_discovery_ids\": [7]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-74160\", \"supporting_discovery_ids\": [2, 3]},\n      {\"term_id\": \"R-HSA-9612973\", \"supporting_discovery_ids\": [1, 6]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [2, 3, 6, 14]},\n      {\"term_id\": \"R-HSA-1266738\", \"supporting_discovery_ids\": [2, 8]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"GCM1\", \"HDAC5\", \"PPM1E\", \"PINK1\", \"PI3K\", \"IMA-3\", \"TAX-6\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":7,"faith_total":7,"faith_pct":100.0}}