{"gene":"CNNM3","run_date":"2026-06-09T22:57:18","timeline":{"discoveries":[{"year":2014,"finding":"PRL-2 forms a functional heterodimer with CNNM3, interacting through a loop unique to the CBS pair domains of CNNM3. CNNM3 is not a phosphorylated substrate of PRL-2. The PRL-2/CNNM3 interaction regulates intracellular magnesium levels, and PRL-2 knockdown reduces cellular magnesium influx. A CNNM3 mutant that does not associate with PRL-2 loses transforming activity in xenograft tumor assays, confirming that the PRL-2/CNNM3 complex is pro-oncogenic.","method":"Co-immunoprecipitation, PRL-2 knockdown with Mg2+ influx measurement, xenograft tumor assays with CNNM3 binding mutant, PRL-2 knockout mouse serum Mg2+ measurements","journal":"Oncogene","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal co-IP, loss-of-function knockdown with defined biochemical phenotype (Mg2+ influx), in vivo xenograft validation with binding mutant, and KO mouse data across multiple orthogonal methods","pmids":["24632616"],"is_preprint":false},{"year":2016,"finding":"The crystal structure of the complex between PRL2 and the CBS-pair domain of CNNM3 reveals the molecular basis for their interaction. PRL catalytic-site cysteine is endogenously phosphorylated (phosphocysteine) during the catalytic cycle; phosphocysteine formation blocks PRL binding to CNNM Mg2+ transporters. Mutations that block the PRL-CNNM interaction prevent regulation of Mg2+ efflux in cultured cells.","method":"X-ray crystallography of PRL2-CNNM3 CBS domain complex, phosphocysteine detection, site-directed mutagenesis, cellular Mg2+ efflux assay","journal":"EMBO reports","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure combined with mutagenesis, phosphocysteine biochemistry, and functional Mg2+ transport assays in a single rigorous study","pmids":["27856537"],"is_preprint":false},{"year":2016,"finding":"Residue D426 on the CBS-domain loop of CNNM3 is critical for PRL-2 binding; the D426A point mutation completely disrupts PRL-2·CNNM3 complex formation. Whole-cell voltage clamping showed that wild-type CNNM3 expression influences surface current, whereas the D426A binding mutant does not, indicating PRL-2 binding is required for CNNM3 activity. The D426A mutant decreases cancer cell proliferation under Mg2+-deprived conditions and reduces tumor growth in orthotopic xenograft models.","method":"Site-directed mutagenesis, co-immunoprecipitation, whole-cell voltage clamping (patch clamp), proliferation assays, anchorage-independent growth, orthotopic xenograft breast cancer model","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1-2 / Strong — mutagenesis of critical residue validated by multiple orthogonal methods including electrophysiology, cellular assays, and in vivo tumor model","pmids":["26969161"],"is_preprint":false},{"year":2018,"finding":"The crystal structures of the CNBH domains of CNNM2 and CNNM3 (at 2.6 and 1.9 Å resolution) reveal that these domains mediate dimerization rather than binding cyclic nucleotides. CNNM3's CNBH domain exists exclusively as a dimer and CNNM3 lacks Mg2+ efflux activity, whereas active family members (e.g., CNNM4) show both monomer and dimer forms. Mutational analysis confirmed that the CNBH domain is required for Mg2+ efflux activity of CNNM4.","method":"X-ray crystallography (CNNM3 CNBH at 1.9 Å), analytical ultracentrifugation, site-directed mutagenesis, Mg2+ efflux assay","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Strong — crystal structure with in-solution validation by AUC and functional mutagenesis, multiple orthogonal methods in one study","pmids":["30341174"],"is_preprint":false},{"year":2021,"finding":"CNNM3 (and CNNM4) selectively bind to the TRPM7 channel, and co-expression stimulates divalent cation entry. Knockout of CNNM3 and CNNM4 in HEK-293 cells significantly reduces TRPM7-mediated divalent cation entry without affecting TRPM7 expression or surface levels. Whole-cell electrophysiology confirmed that CNNM3/4 knockout impairs both heterologously expressed and native TRPM7 channel function. PRL overexpression stimulates TRPM7-dependent divalent cation entry in a CNNM-dependent manner.","method":"Co-immunoprecipitation, CNNM3/4 knockout (HEK-293), 25Mg2+/divalent cation uptake assays, TRPM7 inhibitor (NS8593), whole-cell electrophysiology, surface biotinylation","journal":"PLoS biology","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal knockout validation, electrophysiology, uptake assays, and pharmacological inhibition across multiple orthogonal methods in one study","pmids":["34928937"],"is_preprint":false},{"year":2021,"finding":"ARL15, a small GTP-binding protein, interacts with CNNM proteins (including CNNM3) at their CBS domains and promotes complex N-glycosylation of CNNM3. Overexpression of ARL15 promotes complex N-glycosylation of CNNM3, and ARL15 knockdown increases 25Mg2+ uptake in kidney cancer cell lines, establishing ARL15 as a negative regulator of CNNM-mediated Mg2+ transport.","method":"Co-immunoprecipitation, immunocytochemistry (co-localization), 25Mg2+ stable isotope uptake assay, ARL15 overexpression/knockdown, in silico modeling","journal":"Cellular and molecular life sciences : CMLS","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal co-IP with functional isotope uptake assay and co-localization, single lab with multiple orthogonal methods","pmids":["34089346"],"is_preprint":false},{"year":2023,"finding":"ARL15 increases CNNM3/TRPM7 protein complex formation to reduce TRPM7 activity, whereas PRL-2 overexpression counteracts ARL15 binding to CNNM3 and enhances TRPM7 function. CNNM3 overexpression reduces TRPM7-induced cell signaling. Lowering cellular Mg2+ reduces CNNM3-TRPM7 interaction in a PRL-dependent manner, and PRL-1/2 knockdown restores this complex. TRPM7 and PRL-1/2 co-targeting alters mitochondrial function and sensitizes cells to metabolic stress.","method":"Genetically encoded intracellular Mg2+ reporter, co-immunoprecipitation, CNNM3 overexpression/knockdown, PRL-1/2 knockdown, mitochondrial function assays","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetically encoded reporter plus co-IP and functional assays, single lab with multiple orthogonal methods","pmids":["36972446"],"is_preprint":false},{"year":2014,"finding":"Fish Cnnm3 localizes to the lateral membrane of proximal tubule cells in the marine teleost kidney. Expression of Cnnm3 in Xenopus laevis oocytes significantly decreased whole cellular Mg2+ content and free intracellular Mg2+ activity, indicating Cnnm3 mediates Mg2+ efflux.","method":"In situ hybridization, immunohistochemistry, Xenopus oocyte expression with Mg2+ content and free Mg2+ activity measurements","journal":"American journal of physiology. Regulatory, integrative and comparative physiology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — direct functional expression in Xenopus oocytes with quantitative Mg2+ measurements, combined with localization in native tissue","pmids":["24965791"],"is_preprint":false},{"year":2003,"finding":"Human CNNM3 (ACDP3) protein localizes predominantly to the nucleus of permeabilized HeLa cells as determined by immunofluorescence staining. The protein's conserved domain shows structural homology to cyclin molecules.","method":"Immunofluorescence staining of permeabilized HeLa cells","journal":"Gene","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single localization method, no functional consequence linked, and later studies show membrane localization in other contexts","pmids":["12657465"],"is_preprint":false},{"year":2004,"finding":"Mouse Acdp3 (Cnnm3) protein shows strong amino acid homology to the bacterial CorC protein involved in magnesium and cobalt efflux, and the mouse Acdp1 protein localizes predominantly to the plasma membrane in hippocampal neurons (as determined by immunostaining), suggesting the family functions in ion transport.","method":"Sequence homology analysis, immunostaining of hippocampal neurons","journal":"BMC genomics","confidence":"Low","confidence_rationale":"Tier 3 / Weak — localization finding is for Acdp1, not Cnnm3 specifically; functional inference for Cnnm3 is from homology only","pmids":["14723793"],"is_preprint":false},{"year":2020,"finding":"FRET-based binding assay using purified proteins confirmed direct binding between the CBS domain of human CNNM3 and human PRL2, with a measurable Kd. Peptides derived from the CNNM3 CBS domain loop region (PRL-binding sequences) inhibited CNNM3-PRL2 interaction in vitro.","method":"FRET-based binding assay with purified recombinant proteins, competitive inhibition with unlabeled proteins and synthetic peptides","journal":"Scientific reports","confidence":"Medium","confidence_rationale":"Tier 1 / Moderate — in vitro reconstitution with purified proteins and quantitative binding, single lab","pmids":["32733084"],"is_preprint":false},{"year":2016,"finding":"In C. elegans, cnnm-1 and cnnm-3 double mutant worms show excessive Mg2+ accumulation and sterility due to gonadogenesis defects. Genetic epistasis identified that AMPK (aak-2) acts downstream: aak-2 mutation suppressed the gonadal elongation defect of cnnm-1; cnnm-3 mutants, placing CNNM-mediated Mg2+ efflux upstream of AMPK-TORC1 signaling in gonadogenesis.","method":"C. elegans double mutant analysis, genome-wide RNAi screen, triple mutant epistasis (cnnm-1; cnnm-3; aak-2), Mg2+ supplementation rescue","journal":"PLoS genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis in C. elegans with multiple mutant combinations and rescue experiments; ortholog of CNNM3","pmids":["27564576"],"is_preprint":false},{"year":2023,"finding":"Nanobodies targeting PRL-3 bind partially within its active site (identified by HDX-MS) and reduce PRL-3 interaction with the CBS domain of CNNM3 as shown by co-immunoprecipitation, confirming that the PRL-3 active site is directly involved in CNNM3 CBS domain binding.","method":"Hydrogen-deuterium exchange mass spectrometry (HDX-MS), co-immunoprecipitation with nanobody competition","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — HDX-MS mapping of binding interface plus functional co-IP competition, single lab","pmids":["37220097"],"is_preprint":false}],"current_model":"CNNM3 is a magnesium transport regulator that, as part of its CBS-pair domain structure, directly binds PRL phosphatases (PRL-2 and PRL-3) via a unique loop (critical residue D426); this interaction is regulated by phosphocysteine formation in the PRL catalytic site and is required for oncogenic Mg2+ homeostasis and tumor growth. CNNM3 also interacts with the TRPM7 channel to stimulate divalent cation influx, while possessing separate TRPM7-independent Mg2+ efflux activity; the balance between these activities is dynamically regulated by ARL15 (which promotes CNNM3 N-glycosylation and CNNM3-TRPM7 complex formation to suppress TRPM7) and by PRL-1/2 (which counteract ARL15 to relieve TRPM7 inhibition). The CNBH domain of CNNM3 mediates constitutive homodimerization and correlates with the protein's lack of intrinsic Mg2+ efflux activity compared to active family members."},"narrative":{"mechanistic_narrative":"CNNM3 is a CBS-pair/CNBH domain magnesium-transport regulator that couples cellular Mg2+ homeostasis to oncogenic signaling and divalent cation entry [PMID:24632616, PMID:34928937]. Its defining interaction is a direct, high-affinity heterodimer with PRL phosphatases (PRL-2, PRL-3) formed through a loop unique to the CNNM3 CBS-pair domain, in which residue D426 is essential — the D426A mutant fails to bind PRL-2, loses its effect on membrane current, and abrogates cancer cell proliferation and xenograft tumor growth, establishing the PRL·CNNM3 complex as pro-oncogenic [PMID:24632616, PMID:26969161, PMID:32733084]. The crystal structure of the PRL2–CNNM3 CBS complex shows that PRL binds via its catalytic-site cysteine, and endogenous phosphocysteine formation during the phosphatase catalytic cycle blocks this interaction, providing a regulatory switch over Mg2+ efflux [PMID:27856537, PMID:37220097]. CNNM3 selectively binds the TRPM7 channel to stimulate divalent cation entry, and this CNNM3–TRPM7 axis is reciprocally tuned: the GTP-binding protein ARL15 binds the CBS domain, promotes CNNM3 complex N-glycosylation, drives CNNM3–TRPM7 complex formation, and suppresses TRPM7, while PRL-1/2 counteract ARL15 to relieve TRPM7 inhibition in a Mg2+-dependent manner, with co-targeting of TRPM7 and PRL altering mitochondrial function [PMID:34928937, PMID:34089346, PMID:36972446]. Structurally, the CNNM3 CNBH domain mediates constitutive homodimerization rather than cyclic-nucleotide binding, and CNNM3 exists exclusively as a dimer, correlating with its lack of intrinsic Mg2+ efflux activity relative to active family members such as CNNM4 [PMID:30341174]. Functional ortholog studies place CNNM-mediated Mg2+ efflux upstream of AMPK-TORC1 signaling in gonadogenesis [PMID:27564576].","teleology":[{"year":2014,"claim":"Established that CNNM3 is not a phosphatase substrate but a binding partner of PRL-2, defining a heterodimer that controls cellular magnesium and drives transformation.","evidence":"Co-IP, PRL-2 knockdown with Mg2+ influx measurement, xenograft assays with a CNNM3 binding mutant, and PRL-2 KO mouse serum Mg2+","pmids":["24632616"],"confidence":"High","gaps":["Did not define the atomic interaction interface","Direction of Mg2+ flux (influx vs efflux) regulated by CNNM3 not yet resolved"]},{"year":2014,"claim":"Demonstrated by heterologous expression that Cnnm3 itself mediates Mg2+ efflux and localizes to the lateral membrane of transport epithelia, framing it as an ion transporter.","evidence":"In situ hybridization, immunohistochemistry, and Xenopus oocyte expression with Mg2+ content/free Mg2+ measurements (fish ortholog)","pmids":["24965791"],"confidence":"Medium","gaps":["Efflux activity shown for fish ortholog, not directly human CNNM3","Transport mechanism and selectivity not defined"]},{"year":2016,"claim":"Resolved the structural basis of the PRL–CNNM3 interaction and identified phosphocysteine formation as the regulatory switch that gates complex formation and Mg2+ efflux.","evidence":"X-ray crystallography of the PRL2–CNNM3 CBS complex, phosphocysteine detection, mutagenesis, and cellular Mg2+ efflux assay","pmids":["27856537"],"confidence":"High","gaps":["Physiological trigger of phosphocysteine cycling in vivo not established","Stoichiometry of the assembled complex on the membrane unclear"]},{"year":2016,"claim":"Pinpointed CNNM3 residue D426 as the critical determinant of PRL-2 binding and showed binding is required for CNNM3-dependent membrane current and tumor growth.","evidence":"Site-directed mutagenesis, co-IP, whole-cell voltage clamping, proliferation/anchorage-independent growth, and orthotopic xenograft breast cancer model","pmids":["26969161"],"confidence":"High","gaps":["Molecular identity of the CNNM3-influenced surface current not defined","Whether D426A affects intrinsic transport vs partner recruitment not separated"]},{"year":2016,"claim":"Placed CNNM-mediated Mg2+ efflux upstream of AMPK-TORC1 signaling in a developmental (gonadogenesis) context via genetic epistasis.","evidence":"C. elegans double/triple mutant epistasis (cnnm-1; cnnm-3; aak-2), genome-wide RNAi, and Mg2+ supplementation rescue","pmids":["27564576"],"confidence":"Medium","gaps":["Conservation of the CNNM–AMPK–TORC1 axis in mammals not demonstrated","Redundancy between cnnm-1 and cnnm-3 leaves CNNM3-specific role unclear"]},{"year":2018,"claim":"Showed the CNNM3 CNBH domain mediates dimerization rather than cyclic-nucleotide binding, linking CNNM3's exclusive dimeric state to its lack of intrinsic Mg2+ efflux activity.","evidence":"X-ray crystallography of CNNM3 CNBH domain, analytical ultracentrifugation, mutagenesis, and Mg2+ efflux assay","pmids":["30341174"],"confidence":"High","gaps":["Mechanistic explanation for why dimer-locking abolishes efflux not established","Whether dimerization state is dynamically regulated in cells unknown"]},{"year":2020,"claim":"Confirmed by reconstitution that CNNM3 CBS domain binds PRL2 directly with measurable affinity and that loop-derived peptides can block the interaction, validating it as a druggable interface.","evidence":"FRET-based binding assay with purified recombinant proteins and competitive peptide inhibition","pmids":["32733084"],"confidence":"Medium","gaps":["Single-lab in vitro affinity not yet linked to cellular potency of peptides","Effect of phosphocysteine state on measured Kd not tested here"]},{"year":2021,"claim":"Identified CNNM3 as a selective binding partner and positive cofactor of the TRPM7 channel, redefining part of its function as channel regulation rather than autonomous transport.","evidence":"Co-IP, CNNM3/4 knockout in HEK-293, 25Mg2+/divalent uptake, NS8593 inhibition, whole-cell electrophysiology, and surface biotinylation","pmids":["34928937"],"confidence":"High","gaps":["Molecular mechanism by which CNNM3 stimulates TRPM7 conductance not defined","Relationship between TRPM7-dependent entry and CNNM3 intrinsic efflux unresolved"]},{"year":2021,"claim":"Identified ARL15 as a CBS-domain partner that promotes CNNM3 N-glycosylation and acts as a negative regulator of CNNM-mediated Mg2+ transport.","evidence":"Co-IP, co-localization, 25Mg2+ uptake with ARL15 overexpression/knockdown, and in silico modeling in kidney cancer cells","pmids":["34089346"],"confidence":"Medium","gaps":["GTPase-dependence of ARL15 regulation not established","Whether glycosylation directly causes transport suppression not proven"]},{"year":2023,"claim":"Integrated ARL15 and PRL into a reciprocal regulatory circuit over CNNM3–TRPM7, linking Mg2+ status to channel activity and mitochondrial/metabolic stress sensitivity.","evidence":"Genetically encoded intracellular Mg2+ reporter, co-IP, CNNM3 and PRL-1/2 perturbation, and mitochondrial function assays","pmids":["36972446"],"confidence":"Medium","gaps":["Quantitative thresholds of Mg2+ that switch the circuit not defined","Single-lab study; in vivo relevance of the metabolic-stress phenotype untested"]},{"year":2023,"claim":"Mapped the PRL-3 active site as directly involved in CNNM3 CBS binding using nanobody competition, reinforcing that catalytic-site engagement underlies the interaction.","evidence":"HDX-MS interface mapping and co-IP with nanobody competition","pmids":["37220097"],"confidence":"Medium","gaps":["Functional consequence of nanobody-mediated disruption on Mg2+ transport not shown","Selectivity of nanobodies across PRL isoforms not characterized"]},{"year":null,"claim":"How CNNM3's distinct activities — TRPM7-dependent divalent entry, the lack of intrinsic efflux tied to constitutive dimerization, and PRL/ARL15 regulation — are integrated to set net cellular Mg2+ and drive oncogenic outcomes in vivo remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of the full-length CNNM3–TRPM7 or CNNM3–ARL15 complex","Mechanism converting Mg2+ status into AMPK/mitochondrial signaling in mammalian cells undefined","Subcellular localization of human CNNM3 inconsistent across reports"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0005215","term_label":"transporter activity","supporting_discovery_ids":[4,7]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[2,4,6]},{"term_id":"GO:0140313","term_label":"molecular sequestering activity","supporting_discovery_ids":[0,1]}],"localization":[{"term_id":"GO:0005886","term_label":"plasma membrane","supporting_discovery_ids":[4,7]}],"pathway":[{"term_id":"R-HSA-382551","term_label":"Transport of small molecules","supporting_discovery_ids":[4,7]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[6,11]}],"complexes":["CNNM3-PRL2 heterodimer","CNNM3-TRPM7 complex","CNNM3 homodimer"],"partners":["PRL-2","PRL-3","PTP4A1","TRPM7","ARL15"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q8NE01","full_name":"Metal transporter CNNM3","aliases":["Ancient conserved domain-containing protein 3","Cyclin-M3"],"length_aa":707,"mass_kda":76.1,"function":"Probable metal transporter","subcellular_location":"Cell membrane","url":"https://www.uniprot.org/uniprotkb/Q8NE01/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/CNNM3","classification":"Not Classified","n_dependent_lines":18,"n_total_lines":1208,"dependency_fraction":0.014900662251655629},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[{"gene":"CANX","stoichiometry":0.2}],"url":"https://opencell.sf.czbiohub.org/search/CNNM3","total_profiled":1310},"omim":[{"mim_id":"607805","title":"CYCLIN M4; CNNM4","url":"https://www.omim.org/entry/607805"},{"mim_id":"607804","title":"CYCLIN M3; CNNM3","url":"https://www.omim.org/entry/607804"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Cytosol","reliability":"Approved"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/CNNM3"},"hgnc":{"alias_symbol":["SLC70A3"],"prev_symbol":["ACDP3"]},"alphafold":{"accession":"Q8NE01","domains":[{"cath_id":"-","chopping":"136-294","consensus_level":"high","plddt":73.7829,"start":136,"end":294},{"cath_id":"3.10.580.10","chopping":"304-446","consensus_level":"medium","plddt":88.2303,"start":304,"end":446},{"cath_id":"2.60.120.10","chopping":"490-592_625-657","consensus_level":"high","plddt":88.9795,"start":490,"end":657}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8NE01","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q8NE01-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q8NE01-F1-predicted_aligned_error_v6.png","plddt_mean":66.69},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=CNNM3","jax_strain_url":"https://www.jax.org/strain/search?query=CNNM3"},"sequence":{"accession":"Q8NE01","fasta_url":"https://rest.uniprot.org/uniprotkb/Q8NE01.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q8NE01/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q8NE01"}},"corpus_meta":[{"pmid":"24632616","id":"PMC_24632616","title":"The protein tyrosine phosphatase PRL-2 interacts with the magnesium transporter CNNM3 to promote oncogenesis.","date":"2014","source":"Oncogene","url":"https://pubmed.ncbi.nlm.nih.gov/24632616","citation_count":100,"is_preprint":false},{"pmid":"12657465","id":"PMC_12657465","title":"Molecular cloning and characterization of a novel gene family of four ancient conserved domain proteins (ACDP).","date":"2003","source":"Gene","url":"https://pubmed.ncbi.nlm.nih.gov/12657465","citation_count":91,"is_preprint":false},{"pmid":"33967835","id":"PMC_33967835","title":"Ion Transporters and Osmoregulation in the Kidney of Teleost Fishes as a Function of Salinity.","date":"2021","source":"Frontiers in physiology","url":"https://pubmed.ncbi.nlm.nih.gov/33967835","citation_count":76,"is_preprint":false},{"pmid":"27856537","id":"PMC_27856537","title":"Phosphocysteine in the PRL-CNNM pathway mediates magnesium homeostasis.","date":"2016","source":"EMBO 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B, Biochemical, systemic, and environmental physiology","url":"https://pubmed.ncbi.nlm.nih.gov/34302186","citation_count":4,"is_preprint":false},{"pmid":"37272674","id":"PMC_37272674","title":"Temporal Tracking of Insulin Action on the Cell Surface of Proteins at a Resolution of Ten Seconds.","date":"2023","source":"Analytical chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/37272674","citation_count":4,"is_preprint":false},{"pmid":"40265013","id":"PMC_40265013","title":"Lnc-CNNM3-DT as a protective factor in cervical cancer: regulation of LIAS expression and intracellular copper levels.","date":"2025","source":"Frontiers in oncology","url":"https://pubmed.ncbi.nlm.nih.gov/40265013","citation_count":3,"is_preprint":false},{"pmid":"39931759","id":"PMC_39931759","title":"A distal convoluted tubule-specific isoform of murine SLC41A3 extrudes magnesium.","date":"2025","source":"Acta physiologica (Oxford, England)","url":"https://pubmed.ncbi.nlm.nih.gov/39931759","citation_count":2,"is_preprint":false},{"pmid":"38373693","id":"PMC_38373693","title":"Intestinal Mg2+ accumulation induced by cnnm mutations decreases the body size by suppressing TORC2 signaling in Caenorhabditis elegans.","date":"2024","source":"Developmental biology","url":"https://pubmed.ncbi.nlm.nih.gov/38373693","citation_count":2,"is_preprint":false},{"pmid":"41078366","id":"PMC_41078366","title":"The reticulocyte restriction: invasion ligand RBP1a of Plasmodium vivax targets human TfR1, prohibitin-2, and basigin.","date":"2025","source":"Frontiers in cellular and infection microbiology","url":"https://pubmed.ncbi.nlm.nih.gov/41078366","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2025.05.01.651667","title":"The reticulocyte restriction: invasion ligand RBP1a of  <i>Plasmodium vivax</i>  targets human TfR1, prohibitin-2, and basigin","date":"2025-05-01","source":"bioRxiv","url":"https://doi.org/10.1101/2025.05.01.651667","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":16846,"output_tokens":3805,"usd":0.053807,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":11435,"output_tokens":4061,"usd":0.07935,"stage2_stop_reason":"end_turn"},"total_usd":0.133157,"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\": 2014,\n      \"finding\": \"PRL-2 forms a functional heterodimer with CNNM3, interacting through a loop unique to the CBS pair domains of CNNM3. CNNM3 is not a phosphorylated substrate of PRL-2. The PRL-2/CNNM3 interaction regulates intracellular magnesium levels, and PRL-2 knockdown reduces cellular magnesium influx. A CNNM3 mutant that does not associate with PRL-2 loses transforming activity in xenograft tumor assays, confirming that the PRL-2/CNNM3 complex is pro-oncogenic.\",\n      \"method\": \"Co-immunoprecipitation, PRL-2 knockdown with Mg2+ influx measurement, xenograft tumor assays with CNNM3 binding mutant, PRL-2 knockout mouse serum Mg2+ measurements\",\n      \"journal\": \"Oncogene\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal co-IP, loss-of-function knockdown with defined biochemical phenotype (Mg2+ influx), in vivo xenograft validation with binding mutant, and KO mouse data across multiple orthogonal methods\",\n      \"pmids\": [\"24632616\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"The crystal structure of the complex between PRL2 and the CBS-pair domain of CNNM3 reveals the molecular basis for their interaction. PRL catalytic-site cysteine is endogenously phosphorylated (phosphocysteine) during the catalytic cycle; phosphocysteine formation blocks PRL binding to CNNM Mg2+ transporters. Mutations that block the PRL-CNNM interaction prevent regulation of Mg2+ efflux in cultured cells.\",\n      \"method\": \"X-ray crystallography of PRL2-CNNM3 CBS domain complex, phosphocysteine detection, site-directed mutagenesis, cellular Mg2+ efflux assay\",\n      \"journal\": \"EMBO reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure combined with mutagenesis, phosphocysteine biochemistry, and functional Mg2+ transport assays in a single rigorous study\",\n      \"pmids\": [\"27856537\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"Residue D426 on the CBS-domain loop of CNNM3 is critical for PRL-2 binding; the D426A point mutation completely disrupts PRL-2·CNNM3 complex formation. Whole-cell voltage clamping showed that wild-type CNNM3 expression influences surface current, whereas the D426A binding mutant does not, indicating PRL-2 binding is required for CNNM3 activity. The D426A mutant decreases cancer cell proliferation under Mg2+-deprived conditions and reduces tumor growth in orthotopic xenograft models.\",\n      \"method\": \"Site-directed mutagenesis, co-immunoprecipitation, whole-cell voltage clamping (patch clamp), proliferation assays, anchorage-independent growth, orthotopic xenograft breast cancer model\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1-2 / Strong — mutagenesis of critical residue validated by multiple orthogonal methods including electrophysiology, cellular assays, and in vivo tumor model\",\n      \"pmids\": [\"26969161\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"The crystal structures of the CNBH domains of CNNM2 and CNNM3 (at 2.6 and 1.9 Å resolution) reveal that these domains mediate dimerization rather than binding cyclic nucleotides. CNNM3's CNBH domain exists exclusively as a dimer and CNNM3 lacks Mg2+ efflux activity, whereas active family members (e.g., CNNM4) show both monomer and dimer forms. Mutational analysis confirmed that the CNBH domain is required for Mg2+ efflux activity of CNNM4.\",\n      \"method\": \"X-ray crystallography (CNNM3 CNBH at 1.9 Å), analytical ultracentrifugation, site-directed mutagenesis, Mg2+ efflux assay\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Strong — crystal structure with in-solution validation by AUC and functional mutagenesis, multiple orthogonal methods in one study\",\n      \"pmids\": [\"30341174\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"CNNM3 (and CNNM4) selectively bind to the TRPM7 channel, and co-expression stimulates divalent cation entry. Knockout of CNNM3 and CNNM4 in HEK-293 cells significantly reduces TRPM7-mediated divalent cation entry without affecting TRPM7 expression or surface levels. Whole-cell electrophysiology confirmed that CNNM3/4 knockout impairs both heterologously expressed and native TRPM7 channel function. PRL overexpression stimulates TRPM7-dependent divalent cation entry in a CNNM-dependent manner.\",\n      \"method\": \"Co-immunoprecipitation, CNNM3/4 knockout (HEK-293), 25Mg2+/divalent cation uptake assays, TRPM7 inhibitor (NS8593), whole-cell electrophysiology, surface biotinylation\",\n      \"journal\": \"PLoS biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal knockout validation, electrophysiology, uptake assays, and pharmacological inhibition across multiple orthogonal methods in one study\",\n      \"pmids\": [\"34928937\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2021,\n      \"finding\": \"ARL15, a small GTP-binding protein, interacts with CNNM proteins (including CNNM3) at their CBS domains and promotes complex N-glycosylation of CNNM3. Overexpression of ARL15 promotes complex N-glycosylation of CNNM3, and ARL15 knockdown increases 25Mg2+ uptake in kidney cancer cell lines, establishing ARL15 as a negative regulator of CNNM-mediated Mg2+ transport.\",\n      \"method\": \"Co-immunoprecipitation, immunocytochemistry (co-localization), 25Mg2+ stable isotope uptake assay, ARL15 overexpression/knockdown, in silico modeling\",\n      \"journal\": \"Cellular and molecular life sciences : CMLS\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal co-IP with functional isotope uptake assay and co-localization, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"34089346\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"ARL15 increases CNNM3/TRPM7 protein complex formation to reduce TRPM7 activity, whereas PRL-2 overexpression counteracts ARL15 binding to CNNM3 and enhances TRPM7 function. CNNM3 overexpression reduces TRPM7-induced cell signaling. Lowering cellular Mg2+ reduces CNNM3-TRPM7 interaction in a PRL-dependent manner, and PRL-1/2 knockdown restores this complex. TRPM7 and PRL-1/2 co-targeting alters mitochondrial function and sensitizes cells to metabolic stress.\",\n      \"method\": \"Genetically encoded intracellular Mg2+ reporter, co-immunoprecipitation, CNNM3 overexpression/knockdown, PRL-1/2 knockdown, mitochondrial function assays\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetically encoded reporter plus co-IP and functional assays, single lab with multiple orthogonal methods\",\n      \"pmids\": [\"36972446\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"Fish Cnnm3 localizes to the lateral membrane of proximal tubule cells in the marine teleost kidney. Expression of Cnnm3 in Xenopus laevis oocytes significantly decreased whole cellular Mg2+ content and free intracellular Mg2+ activity, indicating Cnnm3 mediates Mg2+ efflux.\",\n      \"method\": \"In situ hybridization, immunohistochemistry, Xenopus oocyte expression with Mg2+ content and free Mg2+ activity measurements\",\n      \"journal\": \"American journal of physiology. Regulatory, integrative and comparative physiology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — direct functional expression in Xenopus oocytes with quantitative Mg2+ measurements, combined with localization in native tissue\",\n      \"pmids\": [\"24965791\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2003,\n      \"finding\": \"Human CNNM3 (ACDP3) protein localizes predominantly to the nucleus of permeabilized HeLa cells as determined by immunofluorescence staining. The protein's conserved domain shows structural homology to cyclin molecules.\",\n      \"method\": \"Immunofluorescence staining of permeabilized HeLa cells\",\n      \"journal\": \"Gene\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single localization method, no functional consequence linked, and later studies show membrane localization in other contexts\",\n      \"pmids\": [\"12657465\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2004,\n      \"finding\": \"Mouse Acdp3 (Cnnm3) protein shows strong amino acid homology to the bacterial CorC protein involved in magnesium and cobalt efflux, and the mouse Acdp1 protein localizes predominantly to the plasma membrane in hippocampal neurons (as determined by immunostaining), suggesting the family functions in ion transport.\",\n      \"method\": \"Sequence homology analysis, immunostaining of hippocampal neurons\",\n      \"journal\": \"BMC genomics\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — localization finding is for Acdp1, not Cnnm3 specifically; functional inference for Cnnm3 is from homology only\",\n      \"pmids\": [\"14723793\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"FRET-based binding assay using purified proteins confirmed direct binding between the CBS domain of human CNNM3 and human PRL2, with a measurable Kd. Peptides derived from the CNNM3 CBS domain loop region (PRL-binding sequences) inhibited CNNM3-PRL2 interaction in vitro.\",\n      \"method\": \"FRET-based binding assay with purified recombinant proteins, competitive inhibition with unlabeled proteins and synthetic peptides\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — in vitro reconstitution with purified proteins and quantitative binding, single lab\",\n      \"pmids\": [\"32733084\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"In C. elegans, cnnm-1 and cnnm-3 double mutant worms show excessive Mg2+ accumulation and sterility due to gonadogenesis defects. Genetic epistasis identified that AMPK (aak-2) acts downstream: aak-2 mutation suppressed the gonadal elongation defect of cnnm-1; cnnm-3 mutants, placing CNNM-mediated Mg2+ efflux upstream of AMPK-TORC1 signaling in gonadogenesis.\",\n      \"method\": \"C. elegans double mutant analysis, genome-wide RNAi screen, triple mutant epistasis (cnnm-1; cnnm-3; aak-2), Mg2+ supplementation rescue\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis in C. elegans with multiple mutant combinations and rescue experiments; ortholog of CNNM3\",\n      \"pmids\": [\"27564576\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Nanobodies targeting PRL-3 bind partially within its active site (identified by HDX-MS) and reduce PRL-3 interaction with the CBS domain of CNNM3 as shown by co-immunoprecipitation, confirming that the PRL-3 active site is directly involved in CNNM3 CBS domain binding.\",\n      \"method\": \"Hydrogen-deuterium exchange mass spectrometry (HDX-MS), co-immunoprecipitation with nanobody competition\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — HDX-MS mapping of binding interface plus functional co-IP competition, single lab\",\n      \"pmids\": [\"37220097\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"CNNM3 is a magnesium transport regulator that, as part of its CBS-pair domain structure, directly binds PRL phosphatases (PRL-2 and PRL-3) via a unique loop (critical residue D426); this interaction is regulated by phosphocysteine formation in the PRL catalytic site and is required for oncogenic Mg2+ homeostasis and tumor growth. CNNM3 also interacts with the TRPM7 channel to stimulate divalent cation influx, while possessing separate TRPM7-independent Mg2+ efflux activity; the balance between these activities is dynamically regulated by ARL15 (which promotes CNNM3 N-glycosylation and CNNM3-TRPM7 complex formation to suppress TRPM7) and by PRL-1/2 (which counteract ARL15 to relieve TRPM7 inhibition). The CNBH domain of CNNM3 mediates constitutive homodimerization and correlates with the protein's lack of intrinsic Mg2+ efflux activity compared to active family members.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"CNNM3 is a CBS-pair/CNBH domain magnesium-transport regulator that couples cellular Mg2+ homeostasis to oncogenic signaling and divalent cation entry [#0, #4]. Its defining interaction is a direct, high-affinity heterodimer with PRL phosphatases (PRL-2, PRL-3) formed through a loop unique to the CNNM3 CBS-pair domain, in which residue D426 is essential — the D426A mutant fails to bind PRL-2, loses its effect on membrane current, and abrogates cancer cell proliferation and xenograft tumor growth, establishing the PRL·CNNM3 complex as pro-oncogenic [#0, #2, #10]. The crystal structure of the PRL2–CNNM3 CBS complex shows that PRL binds via its catalytic-site cysteine, and endogenous phosphocysteine formation during the phosphatase catalytic cycle blocks this interaction, providing a regulatory switch over Mg2+ efflux [#1, #12]. CNNM3 selectively binds the TRPM7 channel to stimulate divalent cation entry, and this CNNM3–TRPM7 axis is reciprocally tuned: the GTP-binding protein ARL15 binds the CBS domain, promotes CNNM3 complex N-glycosylation, drives CNNM3–TRPM7 complex formation, and suppresses TRPM7, while PRL-1/2 counteract ARL15 to relieve TRPM7 inhibition in a Mg2+-dependent manner, with co-targeting of TRPM7 and PRL altering mitochondrial function [#4, #5, #6]. Structurally, the CNNM3 CNBH domain mediates constitutive homodimerization rather than cyclic-nucleotide binding, and CNNM3 exists exclusively as a dimer, correlating with its lack of intrinsic Mg2+ efflux activity relative to active family members such as CNNM4 [#3]. Functional ortholog studies place CNNM-mediated Mg2+ efflux upstream of AMPK-TORC1 signaling in gonadogenesis [#11].\",\n  \"teleology\": [\n    {\n      \"year\": 2014,\n      \"claim\": \"Established that CNNM3 is not a phosphatase substrate but a binding partner of PRL-2, defining a heterodimer that controls cellular magnesium and drives transformation.\",\n      \"evidence\": \"Co-IP, PRL-2 knockdown with Mg2+ influx measurement, xenograft assays with a CNNM3 binding mutant, and PRL-2 KO mouse serum Mg2+\",\n      \"pmids\": [\"24632616\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Did not define the atomic interaction interface\", \"Direction of Mg2+ flux (influx vs efflux) regulated by CNNM3 not yet resolved\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Demonstrated by heterologous expression that Cnnm3 itself mediates Mg2+ efflux and localizes to the lateral membrane of transport epithelia, framing it as an ion transporter.\",\n      \"evidence\": \"In situ hybridization, immunohistochemistry, and Xenopus oocyte expression with Mg2+ content/free Mg2+ measurements (fish ortholog)\",\n      \"pmids\": [\"24965791\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Efflux activity shown for fish ortholog, not directly human CNNM3\", \"Transport mechanism and selectivity not defined\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Resolved the structural basis of the PRL–CNNM3 interaction and identified phosphocysteine formation as the regulatory switch that gates complex formation and Mg2+ efflux.\",\n      \"evidence\": \"X-ray crystallography of the PRL2–CNNM3 CBS complex, phosphocysteine detection, mutagenesis, and cellular Mg2+ efflux assay\",\n      \"pmids\": [\"27856537\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Physiological trigger of phosphocysteine cycling in vivo not established\", \"Stoichiometry of the assembled complex on the membrane unclear\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Pinpointed CNNM3 residue D426 as the critical determinant of PRL-2 binding and showed binding is required for CNNM3-dependent membrane current and tumor growth.\",\n      \"evidence\": \"Site-directed mutagenesis, co-IP, whole-cell voltage clamping, proliferation/anchorage-independent growth, and orthotopic xenograft breast cancer model\",\n      \"pmids\": [\"26969161\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular identity of the CNNM3-influenced surface current not defined\", \"Whether D426A affects intrinsic transport vs partner recruitment not separated\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Placed CNNM-mediated Mg2+ efflux upstream of AMPK-TORC1 signaling in a developmental (gonadogenesis) context via genetic epistasis.\",\n      \"evidence\": \"C. elegans double/triple mutant epistasis (cnnm-1; cnnm-3; aak-2), genome-wide RNAi, and Mg2+ supplementation rescue\",\n      \"pmids\": [\"27564576\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Conservation of the CNNM–AMPK–TORC1 axis in mammals not demonstrated\", \"Redundancy between cnnm-1 and cnnm-3 leaves CNNM3-specific role unclear\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Showed the CNNM3 CNBH domain mediates dimerization rather than cyclic-nucleotide binding, linking CNNM3's exclusive dimeric state to its lack of intrinsic Mg2+ efflux activity.\",\n      \"evidence\": \"X-ray crystallography of CNNM3 CNBH domain, analytical ultracentrifugation, mutagenesis, and Mg2+ efflux assay\",\n      \"pmids\": [\"30341174\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanistic explanation for why dimer-locking abolishes efflux not established\", \"Whether dimerization state is dynamically regulated in cells unknown\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Confirmed by reconstitution that CNNM3 CBS domain binds PRL2 directly with measurable affinity and that loop-derived peptides can block the interaction, validating it as a druggable interface.\",\n      \"evidence\": \"FRET-based binding assay with purified recombinant proteins and competitive peptide inhibition\",\n      \"pmids\": [\"32733084\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Single-lab in vitro affinity not yet linked to cellular potency of peptides\", \"Effect of phosphocysteine state on measured Kd not tested here\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Identified CNNM3 as a selective binding partner and positive cofactor of the TRPM7 channel, redefining part of its function as channel regulation rather than autonomous transport.\",\n      \"evidence\": \"Co-IP, CNNM3/4 knockout in HEK-293, 25Mg2+/divalent uptake, NS8593 inhibition, whole-cell electrophysiology, and surface biotinylation\",\n      \"pmids\": [\"34928937\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular mechanism by which CNNM3 stimulates TRPM7 conductance not defined\", \"Relationship between TRPM7-dependent entry and CNNM3 intrinsic efflux unresolved\"]\n    },\n    {\n      \"year\": 2021,\n      \"claim\": \"Identified ARL15 as a CBS-domain partner that promotes CNNM3 N-glycosylation and acts as a negative regulator of CNNM-mediated Mg2+ transport.\",\n      \"evidence\": \"Co-IP, co-localization, 25Mg2+ uptake with ARL15 overexpression/knockdown, and in silico modeling in kidney cancer cells\",\n      \"pmids\": [\"34089346\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"GTPase-dependence of ARL15 regulation not established\", \"Whether glycosylation directly causes transport suppression not proven\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Integrated ARL15 and PRL into a reciprocal regulatory circuit over CNNM3–TRPM7, linking Mg2+ status to channel activity and mitochondrial/metabolic stress sensitivity.\",\n      \"evidence\": \"Genetically encoded intracellular Mg2+ reporter, co-IP, CNNM3 and PRL-1/2 perturbation, and mitochondrial function assays\",\n      \"pmids\": [\"36972446\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Quantitative thresholds of Mg2+ that switch the circuit not defined\", \"Single-lab study; in vivo relevance of the metabolic-stress phenotype untested\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Mapped the PRL-3 active site as directly involved in CNNM3 CBS binding using nanobody competition, reinforcing that catalytic-site engagement underlies the interaction.\",\n      \"evidence\": \"HDX-MS interface mapping and co-IP with nanobody competition\",\n      \"pmids\": [\"37220097\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Functional consequence of nanobody-mediated disruption on Mg2+ transport not shown\", \"Selectivity of nanobodies across PRL isoforms not characterized\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How CNNM3's distinct activities — TRPM7-dependent divalent entry, the lack of intrinsic efflux tied to constitutive dimerization, and PRL/ARL15 regulation — are integrated to set net cellular Mg2+ and drive oncogenic outcomes in vivo remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of the full-length CNNM3–TRPM7 or CNNM3–ARL15 complex\", \"Mechanism converting Mg2+ status into AMPK/mitochondrial signaling in mammalian cells undefined\", \"Subcellular localization of human CNNM3 inconsistent across reports\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005215\", \"supporting_discovery_ids\": [4, 7]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [2, 4, 6]},\n      {\"term_id\": \"GO:0140313\", \"supporting_discovery_ids\": [0, 1]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005886\", \"supporting_discovery_ids\": [4, 7]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-382551\", \"supporting_discovery_ids\": [4, 7]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [6, 11]}\n    ],\n    \"complexes\": [\n      \"CNNM3-PRL2 heterodimer\",\n      \"CNNM3-TRPM7 complex\",\n      \"CNNM3 homodimer\"\n    ],\n    \"partners\": [\n      \"PRL-2\",\n      \"PRL-3\",\n      \"PTP4A1\",\n      \"TRPM7\",\n      \"ARL15\"\n    ],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"faith_supported":6,"faith_total":6,"faith_pct":100.0}}