{"gene":"ZFYVE21","run_date":"2026-06-11T09:02:06","timeline":{"discoveries":[{"year":2019,"finding":"ZFYVE21 is a complement-induced Rab5 effector that localizes to MAC+Rab5+ endosomes in a Rab5- and PI(3)P-dependent manner following membrane attack complex (MAC) stimulation, and is post-translationally stabilized there.","method":"Endosomal fractionation, co-localization imaging, pharmacologic PI manipulation","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — multiple orthogonal methods (fractionation, imaging, pharmacologic perturbation) in a single rigorous study with in vivo validation","pmids":["31113953"],"is_preprint":false},{"year":2019,"finding":"ZFYVE21 promotes SMURF2-mediated polyubiquitinylation and proteasome-dependent degradation of endosome-associated PTEN, leading to vesicular enrichment of PI(3,4,5)P3 and sequential recruitment of activated Akt and NF-κB-inducing kinase (NIK) to activate non-canonical NF-κB signaling.","method":"Co-immunoprecipitation, ubiquitinylation assays, pharmacologic perturbation, in vivo humanized mouse model","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP, biochemical ubiquitination assay, in vivo model, multiple orthogonal methods in single rigorous study","pmids":["31113953"],"is_preprint":false},{"year":2010,"finding":"ZF21 (ZFYVE21) localizes to focal adhesions (FAs), binds focal adhesion kinase (FAK), promotes dephosphorylation of FAK at Tyr397, and is required for FA disassembly and cell migration; knockdown increases FA number and delays FA disassembly.","method":"siRNA knockdown, co-immunoprecipitation, immunofluorescence localization, nocodazole-induced FA disassembly assay, migration assays","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 2 / Strong — reciprocal Co-IP, multiple functional assays (migration, FA disassembly), loss-of-function with specific phenotypic readout, replicated across multiple subsequent papers","pmids":["20439989"],"is_preprint":false},{"year":2011,"finding":"ZF21 (ZFYVE21) binds multiple FA-related factors including FAK, β-tubulin, m-calpain, and SHP-2. Its C-terminal region (which forms a novel noncanonical PH-like domain lacking a positively charged phosphoinositide-binding interface as determined by NMR) is sufficient for β-tubulin binding and is required for FA disassembly, cell migration, and experimental lung metastasis.","method":"Co-immunoprecipitation, NMR spectroscopy, deletion mutant functional assays, in vivo mouse lung metastasis model","journal":"The Journal of biological chemistry","confidence":"High","confidence_rationale":"Tier 1 / Moderate — NMR structure determination combined with Co-IP binding assays and functional in vivo validation in a single study","pmids":["21768110"],"is_preprint":false},{"year":2013,"finding":"ZF21 (ZFYVE21) regulates invadopodia-dependent ECM degradation by controlling MT1-MMP accumulation at invadopodia; ZF21 depletion abrogates MT1-MMP localization to invadopodia without affecting overall MMP-2, MMP-9, or MT1-MMP production.","method":"siRNA knockdown, gelatin degradation assays, immunofluorescence of MT1-MMP at invadopodia, zymography","journal":"PloS one","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — loss-of-function with specific subcellular localization readout and functional consequence, single lab, multiple methods","pmids":["23382803"],"is_preprint":false},{"year":2011,"finding":"Proteomic analysis identified 45 ZF21-associated proteins including FA-related proteins and RNA-binding proteins that are components of the spreading initiation center (SIC), suggesting ZF21 may also regulate early cell spreading.","method":"Co-immunoprecipitation followed by mass spectrometry (proteomic analysis)","journal":"Cell adhesion & migration","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single proteomic pulldown without functional validation of most binding partners; hypothesis-generating","pmids":["20890123"],"is_preprint":false},{"year":2020,"finding":"The NH2-terminal region of ZF21 mediates its interaction with FAK; expression of this NH2-terminal fragment as a competitive inhibitor decreases FA turnover, cell migration, invadopodia-dependent ECM degradation, and experimental lung metastasis, establishing that ZF21-FAK interaction is necessary for both FA turnover and invadopodia activity.","method":"Dominant-negative peptide expression, FA turnover assays, Matrigel invasion assay, in vivo mouse lung metastasis model","journal":"Cancer science","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — competitive inhibition of defined protein-protein interaction with multiple functional readouts and in vivo validation, single lab","pmids":["32976654"],"is_preprint":false},{"year":2023,"finding":"ZFYVE21 forms a 'ZRR' complex with Rubicon and RNF34 on early endosomes in a Rab5- and ZFYVE21-dependent manner; within this complex, Rubicon disrupts inhibitory associations between caspase-1 and its pseudosubstrate Flightless I (FliI), while RNF34 ubiquitinylates and degrades FliI, collectively increasing endosome-associated caspase-1 available for NLRP3 inflammasome activation in endothelial cells.","method":"Proteomics of FACS-sorted inflammasomes, co-immunoprecipitation, ubiquitination assays, in vivo mouse models, human tissue validation","journal":"Nature communications","confidence":"High","confidence_rationale":"Tier 2 / Strong — proteomics-informed Co-IP, biochemical ubiquitination assays, three in vivo mouse models, and human tissue validation providing multiple orthogonal lines of evidence","pmids":["37225719"],"is_preprint":false},{"year":2023,"finding":"Hedgehog (Hh) signaling induces ZFYVE21 expression in a subset of memory T cells (CD3+CD4+CD45RO+PTCH1hiPD-1hi); after IFN-γ priming, Hh-induced ZFYVE21 activates NLRP3 inflammasome activity in T cells to potentiate IFN-γ responses and promote chronic vascular inflammation.","method":"Humanized mouse models, primary human T cell culture, Hh ligand stimulation, NLRP3 inflammasome activity assays, T cell-specific ZFYVE21 manipulation","journal":"Science signaling","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — cell-type-specific loss-of-function with defined pathway (Hh→ZFYVE21→NLRP3) and functional readout, single lab, corroborated with patient samples","pmids":["36943921"],"is_preprint":false},{"year":2024,"finding":"In endothelial cells, ZFYVE21 promotes eNOS (ENOS) activity via a Rab5- and Akt-dependent mechanism: it reduces vesicular levels of inhibitory caveolin-1 and facilitates transfer of Golgi-derived eNOS to a perinuclear Rab5+ vesicular population to sustain eNOS activity and vascular barrier function. EC-specific Zfyve21 knockout mice develop reduced eNOS activity, kidney insufficiency, and accelerated aging phenotypes.","method":"EC-specific knockout mice, live cell imaging, human kidney organ cultures, nitric oxide donor rescue, fractionation/localization studies","journal":"Kidney international","confidence":"High","confidence_rationale":"Tier 2 / Strong — EC-specific genetic knockout with defined molecular mechanism (caveolin-1 reduction, eNOS trafficking), live imaging, organ culture, pharmacological rescue, multiple orthogonal methods","pmids":["38797325"],"is_preprint":false}],"current_model":"ZFYVE21 is an endosome-associated Rab5 effector that, via its FYVE domain and a noncanonical C-terminal PH-like domain, localizes to early endosomes in a Rab5- and PI(3)P-dependent manner where it orchestrates multiple signaling axes: in endothelial cells it recruits SMURF2 to degrade PTEN and activate the pAkt–NIK–non-canonical NF-κB pathway, forms a ZRR complex with Rubicon and RNF34 to promote NLRP3 inflammasome activation by degrading the caspase-1 inhibitor FliI, and facilitates Rab5/Akt-dependent trafficking of eNOS to sustain nitric oxide production and vascular barrier function; in adherent/tumor cells it binds FAK, β-tubulin, m-calpain, and SHP-2 at focal adhesions to promote FAK dephosphorylation, focal adhesion disassembly, and MT1-MMP-dependent invadopodia activity driving cell migration and invasion."},"narrative":{"mechanistic_narrative":"ZFYVE21 is an endosome-associated Rab5 effector that couples membrane trafficking to multiple signaling outputs governing vascular inflammation, endothelial homeostasis, and tumor cell motility [PMID:31113953]. It localizes to early endosomes in a Rab5- and PI(3)P-dependent manner following membrane attack complex stimulation, where it is post-translationally stabilized [PMID:31113953]. At these endosomes ZFYVE21 directs SMURF2-mediated polyubiquitinylation and proteasomal degradation of endosomal PTEN, enriching vesicular PI(3,4,5)P3 and recruiting activated Akt and NIK to drive non-canonical NF-κB signaling [PMID:31113953]. It additionally assembles a 'ZRR' complex with Rubicon and RNF34 on early endosomes, in which Rubicon disrupts caspase-1 association with its pseudosubstrate Flightless I and RNF34 ubiquitinylates and degrades FliI, thereby licensing endosome-associated caspase-1 for NLRP3 inflammasome activation in endothelial cells [PMID:37225719]; this inflammasome axis is also engaged downstream of Hedgehog-induced ZFYVE21 in memory T cells to amplify IFN-γ responses [PMID:36943921]. ZFYVE21 further sustains endothelial nitric oxide production by reducing vesicular caveolin-1 and facilitating Rab5/Akt-dependent transfer of Golgi-derived eNOS to a perinuclear vesicular pool, maintaining vascular barrier function [PMID:38797325]. In adherent and tumor cells, ZFYVE21 (ZF21) localizes to focal adhesions and binds FAK, β-tubulin, m-calpain, and SHP-2; through its N-terminal FAK interaction and a C-terminal noncanonical PH-like domain it promotes FAK Tyr397 dephosphorylation, focal adhesion disassembly, MT1-MMP-dependent invadopodia activity, cell migration, and experimental lung metastasis [PMID:20439989, PMID:21768110, PMID:32976654].","teleology":[{"year":2010,"claim":"Established the first molecular function for ZF21/ZFYVE21 by showing it acts at focal adhesions to drive their disassembly, answering how the protein influences cell motility.","evidence":"siRNA knockdown, reciprocal Co-IP with FAK, immunofluorescence, nocodazole-induced FA disassembly and migration assays","pmids":["20439989"],"confidence":"High","gaps":["Does not define which domain mediates FAK binding versus phosphatase recruitment","Mechanism of FAK Tyr397 dephosphorylation (direct vs adaptor) not resolved"]},{"year":2011,"claim":"Defined the binding repertoire and an unusual structural feature, showing ZF21 engages FAK, β-tubulin, m-calpain, and SHP-2 and that its C-terminus is a noncanonical PH-like domain lacking a phosphoinositide-binding interface yet required for migration and metastasis.","evidence":"Co-IP, NMR structure determination of C-terminal domain, deletion-mutant functional assays, in vivo lung metastasis model; complementary proteomic Co-IP/MS identifying 45 partners including SIC RNA-binding proteins","pmids":["21768110","20890123"],"confidence":"High","gaps":["Functional roles of most proteomically identified partners untested","How a PH-like domain without a phosphoinositide interface contributes mechanistically is unexplained"]},{"year":2013,"claim":"Extended ZF21 function from FA disassembly to invasion by showing it controls MT1-MMP delivery to invadopodia, linking it to ECM degradation.","evidence":"siRNA knockdown, gelatin degradation assays, MT1-MMP immunofluorescence, zymography","pmids":["23382803"],"confidence":"Medium","gaps":["How ZF21 directs MT1-MMP localization without altering its production is unknown","Single lab, no in vivo confirmation in this study"]},{"year":2019,"claim":"Reframed ZFYVE21 as an endosomal Rab5 effector and connected it to inflammatory signaling, showing it degrades endosomal PTEN via SMURF2 to activate Akt–NIK–non-canonical NF-κB after complement attack.","evidence":"Endosomal fractionation, co-localization imaging, pharmacologic PI manipulation, reciprocal Co-IP, ubiquitination assays, humanized mouse model","pmids":["31113953"],"confidence":"High","gaps":["Relationship between the endosomal signaling role and the focal-adhesion role is unintegrated","Stoichiometry and direct binding within the ZFYVE21–SMURF2–PTEN module not fully resolved"]},{"year":2020,"claim":"Mapped the FAK-binding determinant to the ZF21 N-terminus and demonstrated, via competitive inhibition, that this interaction is necessary for both FA turnover and invadopodia activity.","evidence":"Dominant-negative N-terminal peptide expression, FA turnover assays, Matrigel invasion, in vivo lung metastasis model","pmids":["32976654"],"confidence":"Medium","gaps":["Whether the N-terminal fragment acts solely by blocking FAK binding is not excluded","Does not address endosomal functions of the N-terminus"]},{"year":2023,"claim":"Identified a defined inflammasome-activating complex (ZRR) and a Hedgehog-driven T cell circuit, explaining how endosomal ZFYVE21 promotes NLRP3 activation in two cell types.","evidence":"Inflammasome proteomics, Co-IP, ubiquitination assays, multiple in vivo mouse models and human tissue (ZRR/FliI); humanized mice, primary T cell culture, Hh stimulation, T cell-specific manipulation (Hh axis)","pmids":["37225719","36943921"],"confidence":"High","gaps":["Direct binding topology within the Rubicon–RNF34–ZFYVE21 complex not fully mapped","Whether the T cell and endothelial inflammasome mechanisms are identical is untested"]},{"year":2024,"claim":"Demonstrated a vascular-protective trafficking role, showing ZFYVE21 sustains eNOS activity by lowering inhibitory caveolin-1 and routing Golgi-derived eNOS to Rab5+ vesicles, with loss causing kidney insufficiency and accelerated aging.","evidence":"EC-specific knockout mice, live-cell imaging, human kidney organ cultures, nitric oxide donor rescue, fractionation/localization","pmids":["38797325"],"confidence":"High","gaps":["Mechanism by which ZFYVE21 reduces vesicular caveolin-1 is unspecified","Connection to its PTEN/NF-κB and inflammasome axes within the same cell not delineated"]},{"year":null,"claim":"How a single endosomal Rab5 effector is partitioned between its focal-adhesion/invadopodia functions and its distinct endosomal signaling complexes (PTEN/NF-κB, ZRR/inflammasome, eNOS trafficking) within a given cell remains unresolved.","evidence":"","pmids":[],"confidence":"High","gaps":["No unified model linking the cytoskeletal and endosomal activities","Domain-level rules governing which partner complex assembles in which context are unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[1,2,7]},{"term_id":"GO:0008289","term_label":"lipid binding","supporting_discovery_ids":[0]},{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[3]}],"localization":[{"term_id":"GO:0005768","term_label":"endosome","supporting_discovery_ids":[0,1,7,9]},{"term_id":"GO:0005856","term_label":"cytoskeleton","supporting_discovery_ids":[2,3]}],"pathway":[{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[7,8]},{"term_id":"R-HSA-5653656","term_label":"Vesicle-mediated transport","supporting_discovery_ids":[9]},{"term_id":"R-HSA-1474244","term_label":"Extracellular matrix organization","supporting_discovery_ids":[4]},{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[1]}],"complexes":["ZRR complex (ZFYVE21-Rubicon-RNF34)"],"partners":["FAK","SMURF2","PTEN","RUBCN","RNF34","SHP-2","TUBB","CAPN2"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9BQ24","full_name":"Zinc finger FYVE domain-containing protein 21","aliases":[],"length_aa":234,"mass_kda":26.5,"function":"Plays a role in cell adhesion, and thereby in cell motility which requires repeated formation and disassembly of focal adhesions. Regulates microtubule-induced PTK2/FAK1 dephosphorylation, an event important for focal adhesion disassembly, as well as integrin beta-1/ITGB1 cell surface expression","subcellular_location":"Cell junction, focal adhesion; Cytoplasmic vesicle; Endosome","url":"https://www.uniprot.org/uniprotkb/Q9BQ24/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ZFYVE21","classification":"Not Classified","n_dependent_lines":3,"n_total_lines":1208,"dependency_fraction":0.0024834437086092716},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/ZFYVE21","total_profiled":1310},"omim":[{"mim_id":"613504","title":"ZINC FINGER FYVE DOMAIN-CONTAINING PROTEIN 21; ZFYVE21","url":"https://www.omim.org/entry/613504"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/ZFYVE21"},"hgnc":{"alias_symbol":["MGC2550","ZF21"],"prev_symbol":[]},"alphafold":{"accession":"Q9BQ24","domains":[{"cath_id":"3.30.40.10","chopping":"19-113","consensus_level":"high","plddt":96.0183,"start":19,"end":113},{"cath_id":"2.30.29.160","chopping":"121-165_184-234","consensus_level":"high","plddt":91.5478,"start":121,"end":234}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9BQ24","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9BQ24-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9BQ24-F1-predicted_aligned_error_v6.png","plddt_mean":91.0},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ZFYVE21","jax_strain_url":"https://www.jax.org/strain/search?query=ZFYVE21"},"sequence":{"accession":"Q9BQ24","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9BQ24.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9BQ24/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9BQ24"}},"corpus_meta":[{"pmid":"31113953","id":"PMC_31113953","title":"ZFYVE21 is a complement-induced Rab5 effector that activates non-canonical NF-κB via phosphoinosotide remodeling of endosomes.","date":"2019","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/31113953","citation_count":35,"is_preprint":false},{"pmid":"2902580","id":"PMC_2902580","title":"Primary structure, developmentally regulated expression and potential duplication of the zebrafish homeobox gene ZF-21.","date":"1988","source":"Nucleic acids research","url":"https://pubmed.ncbi.nlm.nih.gov/2902580","citation_count":30,"is_preprint":false},{"pmid":"20439989","id":"PMC_20439989","title":"ZF21 protein regulates cell adhesion and motility.","date":"2010","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/20439989","citation_count":20,"is_preprint":false},{"pmid":"21768110","id":"PMC_21768110","title":"ZF21 protein, a regulator of the disassembly of focal adhesions and cancer metastasis, contains a novel noncanonical pleckstrin homology domain.","date":"2011","source":"The Journal of biological chemistry","url":"https://pubmed.ncbi.nlm.nih.gov/21768110","citation_count":13,"is_preprint":false},{"pmid":"36943921","id":"PMC_36943921","title":"Hedgehog-induced ZFYVE21 promotes chronic vascular inflammation by activating NLRP3 inflammasomes in T cells.","date":"2023","source":"Science signaling","url":"https://pubmed.ncbi.nlm.nih.gov/36943921","citation_count":11,"is_preprint":false},{"pmid":"32976654","id":"PMC_32976654","title":"NH2 -terminal fragment of ZF21 protein suppresses tumor invasion via inhibiting the interaction of ZF21 with FAK.","date":"2020","source":"Cancer science","url":"https://pubmed.ncbi.nlm.nih.gov/32976654","citation_count":9,"is_preprint":false},{"pmid":"23382803","id":"PMC_23382803","title":"The phosphoinositide-binding protein ZF21 regulates ECM degradation by invadopodia.","date":"2013","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/23382803","citation_count":7,"is_preprint":false},{"pmid":"20890123","id":"PMC_20890123","title":"ZF21 is a new regulator of focal adhesion disassembly and a potential member of the spreading initiation center.","date":"2011","source":"Cell adhesion & migration","url":"https://pubmed.ncbi.nlm.nih.gov/20890123","citation_count":7,"is_preprint":false},{"pmid":"37225719","id":"PMC_37225719","title":"A ZFYVE21-Rubicon-RNF34 signaling complex promotes endosome-associated inflammasome activity in endothelial cells.","date":"2023","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/37225719","citation_count":6,"is_preprint":false},{"pmid":"38797325","id":"PMC_38797325","title":"ZFYVE21 promotes endothelial nitric oxide signaling and vascular barrier function in the kidney during aging.","date":"2024","source":"Kidney international","url":"https://pubmed.ncbi.nlm.nih.gov/38797325","citation_count":5,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":6889,"output_tokens":2689,"usd":0.030501,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":9929,"output_tokens":3376,"usd":0.067022,"stage2_stop_reason":"end_turn"},"total_usd":0.097523,"stage1_batch_id":"msgbatch_01UT1AahFPCAyn2uVweS7A9z","stage2_batch_id":"msgbatch_01HuKWtKNT4Pqj1bc8eEP5RV","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2019,\n      \"finding\": \"ZFYVE21 is a complement-induced Rab5 effector that localizes to MAC+Rab5+ endosomes in a Rab5- and PI(3)P-dependent manner following membrane attack complex (MAC) stimulation, and is post-translationally stabilized there.\",\n      \"method\": \"Endosomal fractionation, co-localization imaging, pharmacologic PI manipulation\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — multiple orthogonal methods (fractionation, imaging, pharmacologic perturbation) in a single rigorous study with in vivo validation\",\n      \"pmids\": [\"31113953\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2019,\n      \"finding\": \"ZFYVE21 promotes SMURF2-mediated polyubiquitinylation and proteasome-dependent degradation of endosome-associated PTEN, leading to vesicular enrichment of PI(3,4,5)P3 and sequential recruitment of activated Akt and NF-κB-inducing kinase (NIK) to activate non-canonical NF-κB signaling.\",\n      \"method\": \"Co-immunoprecipitation, ubiquitinylation assays, pharmacologic perturbation, in vivo humanized mouse model\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP, biochemical ubiquitination assay, in vivo model, multiple orthogonal methods in single rigorous study\",\n      \"pmids\": [\"31113953\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"ZF21 (ZFYVE21) localizes to focal adhesions (FAs), binds focal adhesion kinase (FAK), promotes dephosphorylation of FAK at Tyr397, and is required for FA disassembly and cell migration; knockdown increases FA number and delays FA disassembly.\",\n      \"method\": \"siRNA knockdown, co-immunoprecipitation, immunofluorescence localization, nocodazole-induced FA disassembly assay, migration assays\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — reciprocal Co-IP, multiple functional assays (migration, FA disassembly), loss-of-function with specific phenotypic readout, replicated across multiple subsequent papers\",\n      \"pmids\": [\"20439989\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"ZF21 (ZFYVE21) binds multiple FA-related factors including FAK, β-tubulin, m-calpain, and SHP-2. Its C-terminal region (which forms a novel noncanonical PH-like domain lacking a positively charged phosphoinositide-binding interface as determined by NMR) is sufficient for β-tubulin binding and is required for FA disassembly, cell migration, and experimental lung metastasis.\",\n      \"method\": \"Co-immunoprecipitation, NMR spectroscopy, deletion mutant functional assays, in vivo mouse lung metastasis model\",\n      \"journal\": \"The Journal of biological chemistry\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 / Moderate — NMR structure determination combined with Co-IP binding assays and functional in vivo validation in a single study\",\n      \"pmids\": [\"21768110\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2013,\n      \"finding\": \"ZF21 (ZFYVE21) regulates invadopodia-dependent ECM degradation by controlling MT1-MMP accumulation at invadopodia; ZF21 depletion abrogates MT1-MMP localization to invadopodia without affecting overall MMP-2, MMP-9, or MT1-MMP production.\",\n      \"method\": \"siRNA knockdown, gelatin degradation assays, immunofluorescence of MT1-MMP at invadopodia, zymography\",\n      \"journal\": \"PloS one\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — loss-of-function with specific subcellular localization readout and functional consequence, single lab, multiple methods\",\n      \"pmids\": [\"23382803\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2011,\n      \"finding\": \"Proteomic analysis identified 45 ZF21-associated proteins including FA-related proteins and RNA-binding proteins that are components of the spreading initiation center (SIC), suggesting ZF21 may also regulate early cell spreading.\",\n      \"method\": \"Co-immunoprecipitation followed by mass spectrometry (proteomic analysis)\",\n      \"journal\": \"Cell adhesion & migration\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single proteomic pulldown without functional validation of most binding partners; hypothesis-generating\",\n      \"pmids\": [\"20890123\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"The NH2-terminal region of ZF21 mediates its interaction with FAK; expression of this NH2-terminal fragment as a competitive inhibitor decreases FA turnover, cell migration, invadopodia-dependent ECM degradation, and experimental lung metastasis, establishing that ZF21-FAK interaction is necessary for both FA turnover and invadopodia activity.\",\n      \"method\": \"Dominant-negative peptide expression, FA turnover assays, Matrigel invasion assay, in vivo mouse lung metastasis model\",\n      \"journal\": \"Cancer science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — competitive inhibition of defined protein-protein interaction with multiple functional readouts and in vivo validation, single lab\",\n      \"pmids\": [\"32976654\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"ZFYVE21 forms a 'ZRR' complex with Rubicon and RNF34 on early endosomes in a Rab5- and ZFYVE21-dependent manner; within this complex, Rubicon disrupts inhibitory associations between caspase-1 and its pseudosubstrate Flightless I (FliI), while RNF34 ubiquitinylates and degrades FliI, collectively increasing endosome-associated caspase-1 available for NLRP3 inflammasome activation in endothelial cells.\",\n      \"method\": \"Proteomics of FACS-sorted inflammasomes, co-immunoprecipitation, ubiquitination assays, in vivo mouse models, human tissue validation\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — proteomics-informed Co-IP, biochemical ubiquitination assays, three in vivo mouse models, and human tissue validation providing multiple orthogonal lines of evidence\",\n      \"pmids\": [\"37225719\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Hedgehog (Hh) signaling induces ZFYVE21 expression in a subset of memory T cells (CD3+CD4+CD45RO+PTCH1hiPD-1hi); after IFN-γ priming, Hh-induced ZFYVE21 activates NLRP3 inflammasome activity in T cells to potentiate IFN-γ responses and promote chronic vascular inflammation.\",\n      \"method\": \"Humanized mouse models, primary human T cell culture, Hh ligand stimulation, NLRP3 inflammasome activity assays, T cell-specific ZFYVE21 manipulation\",\n      \"journal\": \"Science signaling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — cell-type-specific loss-of-function with defined pathway (Hh→ZFYVE21→NLRP3) and functional readout, single lab, corroborated with patient samples\",\n      \"pmids\": [\"36943921\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"In endothelial cells, ZFYVE21 promotes eNOS (ENOS) activity via a Rab5- and Akt-dependent mechanism: it reduces vesicular levels of inhibitory caveolin-1 and facilitates transfer of Golgi-derived eNOS to a perinuclear Rab5+ vesicular population to sustain eNOS activity and vascular barrier function. EC-specific Zfyve21 knockout mice develop reduced eNOS activity, kidney insufficiency, and accelerated aging phenotypes.\",\n      \"method\": \"EC-specific knockout mice, live cell imaging, human kidney organ cultures, nitric oxide donor rescue, fractionation/localization studies\",\n      \"journal\": \"Kidney international\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — EC-specific genetic knockout with defined molecular mechanism (caveolin-1 reduction, eNOS trafficking), live imaging, organ culture, pharmacological rescue, multiple orthogonal methods\",\n      \"pmids\": [\"38797325\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"ZFYVE21 is an endosome-associated Rab5 effector that, via its FYVE domain and a noncanonical C-terminal PH-like domain, localizes to early endosomes in a Rab5- and PI(3)P-dependent manner where it orchestrates multiple signaling axes: in endothelial cells it recruits SMURF2 to degrade PTEN and activate the pAkt–NIK–non-canonical NF-κB pathway, forms a ZRR complex with Rubicon and RNF34 to promote NLRP3 inflammasome activation by degrading the caspase-1 inhibitor FliI, and facilitates Rab5/Akt-dependent trafficking of eNOS to sustain nitric oxide production and vascular barrier function; in adherent/tumor cells it binds FAK, β-tubulin, m-calpain, and SHP-2 at focal adhesions to promote FAK dephosphorylation, focal adhesion disassembly, and MT1-MMP-dependent invadopodia activity driving cell migration and invasion.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"ZFYVE21 is an endosome-associated Rab5 effector that couples membrane trafficking to multiple signaling outputs governing vascular inflammation, endothelial homeostasis, and tumor cell motility [#0, #1]. It localizes to early endosomes in a Rab5- and PI(3)P-dependent manner following membrane attack complex stimulation, where it is post-translationally stabilized [#0]. At these endosomes ZFYVE21 directs SMURF2-mediated polyubiquitinylation and proteasomal degradation of endosomal PTEN, enriching vesicular PI(3,4,5)P3 and recruiting activated Akt and NIK to drive non-canonical NF-\\u03baB signaling [#1]. It additionally assembles a 'ZRR' complex with Rubicon and RNF34 on early endosomes, in which Rubicon disrupts caspase-1 association with its pseudosubstrate Flightless I and RNF34 ubiquitinylates and degrades FliI, thereby licensing endosome-associated caspase-1 for NLRP3 inflammasome activation in endothelial cells [#7]; this inflammasome axis is also engaged downstream of Hedgehog-induced ZFYVE21 in memory T cells to amplify IFN-\\u03b3 responses [#8]. ZFYVE21 further sustains endothelial nitric oxide production by reducing vesicular caveolin-1 and facilitating Rab5/Akt-dependent transfer of Golgi-derived eNOS to a perinuclear vesicular pool, maintaining vascular barrier function [#9]. In adherent and tumor cells, ZFYVE21 (ZF21) localizes to focal adhesions and binds FAK, \\u03b2-tubulin, m-calpain, and SHP-2; through its N-terminal FAK interaction and a C-terminal noncanonical PH-like domain it promotes FAK Tyr397 dephosphorylation, focal adhesion disassembly, MT1-MMP-dependent invadopodia activity, cell migration, and experimental lung metastasis [#2, #3, #6].\",\n  \"teleology\": [\n    {\n      \"year\": 2010,\n      \"claim\": \"Established the first molecular function for ZF21/ZFYVE21 by showing it acts at focal adhesions to drive their disassembly, answering how the protein influences cell motility.\",\n      \"evidence\": \"siRNA knockdown, reciprocal Co-IP with FAK, immunofluorescence, nocodazole-induced FA disassembly and migration assays\",\n      \"pmids\": [\"20439989\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Does not define which domain mediates FAK binding versus phosphatase recruitment\", \"Mechanism of FAK Tyr397 dephosphorylation (direct vs adaptor) not resolved\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Defined the binding repertoire and an unusual structural feature, showing ZF21 engages FAK, \\u03b2-tubulin, m-calpain, and SHP-2 and that its C-terminus is a noncanonical PH-like domain lacking a phosphoinositide-binding interface yet required for migration and metastasis.\",\n      \"evidence\": \"Co-IP, NMR structure determination of C-terminal domain, deletion-mutant functional assays, in vivo lung metastasis model; complementary proteomic Co-IP/MS identifying 45 partners including SIC RNA-binding proteins\",\n      \"pmids\": [\"21768110\", \"20890123\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Functional roles of most proteomically identified partners untested\", \"How a PH-like domain without a phosphoinositide interface contributes mechanistically is unexplained\"]\n    },\n    {\n      \"year\": 2013,\n      \"claim\": \"Extended ZF21 function from FA disassembly to invasion by showing it controls MT1-MMP delivery to invadopodia, linking it to ECM degradation.\",\n      \"evidence\": \"siRNA knockdown, gelatin degradation assays, MT1-MMP immunofluorescence, zymography\",\n      \"pmids\": [\"23382803\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"How ZF21 directs MT1-MMP localization without altering its production is unknown\", \"Single lab, no in vivo confirmation in this study\"]\n    },\n    {\n      \"year\": 2019,\n      \"claim\": \"Reframed ZFYVE21 as an endosomal Rab5 effector and connected it to inflammatory signaling, showing it degrades endosomal PTEN via SMURF2 to activate Akt\\u2013NIK\\u2013non-canonical NF-\\u03baB after complement attack.\",\n      \"evidence\": \"Endosomal fractionation, co-localization imaging, pharmacologic PI manipulation, reciprocal Co-IP, ubiquitination assays, humanized mouse model\",\n      \"pmids\": [\"31113953\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Relationship between the endosomal signaling role and the focal-adhesion role is unintegrated\", \"Stoichiometry and direct binding within the ZFYVE21\\u2013SMURF2\\u2013PTEN module not fully resolved\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Mapped the FAK-binding determinant to the ZF21 N-terminus and demonstrated, via competitive inhibition, that this interaction is necessary for both FA turnover and invadopodia activity.\",\n      \"evidence\": \"Dominant-negative N-terminal peptide expression, FA turnover assays, Matrigel invasion, in vivo lung metastasis model\",\n      \"pmids\": [\"32976654\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether the N-terminal fragment acts solely by blocking FAK binding is not excluded\", \"Does not address endosomal functions of the N-terminus\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Identified a defined inflammasome-activating complex (ZRR) and a Hedgehog-driven T cell circuit, explaining how endosomal ZFYVE21 promotes NLRP3 activation in two cell types.\",\n      \"evidence\": \"Inflammasome proteomics, Co-IP, ubiquitination assays, multiple in vivo mouse models and human tissue (ZRR/FliI); humanized mice, primary T cell culture, Hh stimulation, T cell-specific manipulation (Hh axis)\",\n      \"pmids\": [\"37225719\", \"36943921\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct binding topology within the Rubicon\\u2013RNF34\\u2013ZFYVE21 complex not fully mapped\", \"Whether the T cell and endothelial inflammasome mechanisms are identical is untested\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Demonstrated a vascular-protective trafficking role, showing ZFYVE21 sustains eNOS activity by lowering inhibitory caveolin-1 and routing Golgi-derived eNOS to Rab5+ vesicles, with loss causing kidney insufficiency and accelerated aging.\",\n      \"evidence\": \"EC-specific knockout mice, live-cell imaging, human kidney organ cultures, nitric oxide donor rescue, fractionation/localization\",\n      \"pmids\": [\"38797325\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Mechanism by which ZFYVE21 reduces vesicular caveolin-1 is unspecified\", \"Connection to its PTEN/NF-\\u03baB and inflammasome axes within the same cell not delineated\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How a single endosomal Rab5 effector is partitioned between its focal-adhesion/invadopodia functions and its distinct endosomal signaling complexes (PTEN/NF-\\u03baB, ZRR/inflammasome, eNOS trafficking) within a given cell remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No unified model linking the cytoskeletal and endosomal activities\", \"Domain-level rules governing which partner complex assembles in which context are unknown\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [1, 2, 7]},\n      {\"term_id\": \"GO:0008289\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [3]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005768\", \"supporting_discovery_ids\": [0, 1, 7, 9]},\n      {\"term_id\": \"GO:0005769\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0005856\", \"supporting_discovery_ids\": [2, 3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0162582\", \"supporting_discovery_ids\": [1]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [7, 8]},\n      {\"term_id\": \"R-HSA-5653656\", \"supporting_discovery_ids\": [9]},\n      {\"term_id\": \"R-HSA-1474244\", \"supporting_discovery_ids\": [4]},\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [1]}\n    ],\n    \"complexes\": [\"ZRR complex (ZFYVE21-Rubicon-RNF34)\"],\n    \"partners\": [\"FAK\", \"SMURF2\", \"PTEN\", \"RUBCN\", \"RNF34\", \"SHP-2\", \"TUBB\", \"CAPN2\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":5,"faith_total":6,"faith_pct":83.33333333333333}}