{"gene":"ENKD1","run_date":"2026-04-28T17:46:03","timeline":{"discoveries":[{"year":2022,"finding":"ENKD1 localizes to the centrosome throughout ciliogenesis and competes with CEP97 for binding to CP110, thereby displacing CP110 from the mother centriole to initiate ciliogenesis. ENKD1 depletion enhances the CP110-CEP97 interaction and retains CP110 at the mother centriole, blocking cilium formation. Simultaneous knockdown of ENKD1 and CP110 rescues ciliogenesis defects caused by ENKD1 depletion.","method":"Knockout mice, super-resolution microscopy, protein interaction/competition assays (Co-IP), double knockdown epistasis, cellular ciliogenesis assays","journal":"EMBO reports","confidence":"High","confidence_rationale":"Tier 2 — reciprocal protein interaction, epistasis with double KD, KO mouse phenotype, multiple orthogonal methods","pmids":["35301795"],"is_preprint":false},{"year":2022,"finding":"ENKD1 is a microtubule-binding protein that stabilizes astral microtubules to orient the mitotic spindle in basal keratinocytes. ENKD1 depletion impairs spindle orientation and delays mitotic progression; re-introduction of the ENKD1 microtubule-binding domain rescues spindle orientation defects. Loss of ENKD1 in mice leads to thinner epidermis due to reduced asymmetric division of basal keratinocytes.","method":"Knockout mice, domain-rescue experiments, microtubule co-sedimentation/binding assays, live-cell imaging of spindle orientation, mitosis timing assays","journal":"Cell death and differentiation","confidence":"High","confidence_rationale":"Tier 1–2 — microtubule-binding assay, domain rescue, KO mouse phenotype, multiple orthogonal methods","pmids":["35197565"],"is_preprint":false},{"year":2022,"finding":"ENKD1 is a MAP component of the centriole wall and ciliary axoneme. In vitro and cellular assays show ENKD1 promotes tubulin polymerization and microtubule stability; ENKD1 overexpression disrupts microtubule organization, and ENKD1 depletion impairs ciliary length and content regulation and prevents Hedgehog pathway activation in response to stimulation.","method":"In vitro tubulin polymerization assay, cellular microtubule stability assays, proximity-interaction proteomics, siRNA knockdown with ciliary length/content measurement, Hedgehog pathway reporter assays","journal":"The FEBS journal","confidence":"High","confidence_rationale":"Tier 1–2 — in vitro reconstitution of MAP activity, proximity interactome, multiple cellular assays","pmids":["35072334"],"is_preprint":false},{"year":2024,"finding":"The deubiquitinase CYLD interacts with ENKD1 and deubiquitinates it at lysine residues K141 and K242. Deubiquitinated ENKD1 then interacts with Ezrin and promotes its microvillar localization in retinal pigment epithelium (RPE) cells, which is required for phagocytosis of photoreceptor outer segments. CYLD-deficient mice have abnormal retinal structure and impaired phagocytic function.","method":"Co-IP, ubiquitination assays with site-directed mutagenesis (K141, K242), CYLD knockout mice, retinal phenotype analysis, Ezrin localization imaging","journal":"Advanced science (Weinheim, Baden-Wurttemberg, Germany)","confidence":"High","confidence_rationale":"Tier 1–2 — mutagenesis of ubiquitination sites, KO mouse phenotype, reciprocal Co-IP, multiple orthogonal methods","pmids":["39373352"],"is_preprint":false},{"year":2025,"finding":"HDAC6 deacetylates ENKD1 at lysine 98, which impairs ENKD1's interaction with γ-tubulin and restrains ENKD1's centrosomal localization, thereby disrupting mitotic spindle orientation and positioning in corneal epithelial cells.","method":"Acetylation site mutagenesis (K98), Co-IP, HDAC6 overexpression in mice, centrosomal localization imaging, spindle orientation assays","journal":"EMBO reports","confidence":"High","confidence_rationale":"Tier 1–2 — site-specific mutagenesis, Co-IP of ENKD1-γ-tubulin interaction, in vivo mouse model, multiple methods","pmids":["40155750"],"is_preprint":false},{"year":2025,"finding":"ENKD1 interacts with geranylgeranyl diphosphate synthase 1 (GGPS1) and modulates its enzymatic activity, reducing geranylgeranyl diphosphate production, which leads to RAC1 inactivation and suppression of pro-inflammatory signaling downstream of TLR activation. ENKD1 deletion enhances innate immune activation and exacerbates septic inflammation.","method":"Co-IP, GGPS1 enzymatic activity assay, ENKD1 knockout cells/mice, RAC1 activation assay, TLR signaling assays","journal":"Cell reports","confidence":"High","confidence_rationale":"Tier 1–2 — enzymatic activity modulation assay, KO mouse phenotype, Co-IP, RAC1 activity measurement","pmids":["40048432"],"is_preprint":false},{"year":2025,"finding":"ENKD1 interacts with the E3 ubiquitin ligase TRIM21, which mediates K48-linked polyubiquitination and degradation of RUBCN (Run domain Beclin-1-interacting and cysteine-rich domain-containing protein), thereby dampening RUBCN's role in LC3-associated phagocytosis (LAP). ENKD1-deficient macrophages show enhanced LAP, increased ROS, and improved phagosome-lysosome fusion, while ENKD1-deficient mice show improved bacterial clearance.","method":"Co-IP, ubiquitination assay (K48-linked), ENKD1 KO macrophages, in vivo bacterial infection models, LC3 lipidation assays, phagosome-lysosome fusion assays","journal":"Proceedings of the National Academy of Sciences of the United States of America","confidence":"High","confidence_rationale":"Tier 1–2 — ubiquitination linkage assay, KO mouse in vivo model, multiple mechanistic assays, reciprocal Co-IP","pmids":["41187080"],"is_preprint":false},{"year":2025,"finding":"ENKD1 localizes to centrosomes and microtubules in basal keratinocytes and enhances microtubule stability, at least in part through EB1. Loss of ENKD1 destabilizes microtubules, impedes keratinocyte migration, and reduces epidermal elasticity in knockout mice.","method":"Enkd1 knockout mice, microtubule stability assays, keratinocyte migration assays, localization imaging, EB1 interaction analysis","journal":"Cytoskeleton (Hoboken, N.J.)","confidence":"Medium","confidence_rationale":"Tier 2–3 — KO mouse phenotype, microtubule stability assay, EB1 interaction suggested but not fully characterized","pmids":["40879264"],"is_preprint":false}],"current_model":"ENKD1 is a centrosomal microtubule-associated protein that stabilizes astral and centriolar microtubules, regulates ciliogenesis by competing with CEP97 to displace CP110 from the mother centriole, orients the mitotic spindle via astral microtubule stabilization, is subject to post-translational regulation by CYLD-mediated deubiquitination (at K141/K242, promoting Ezrin localization) and HDAC6-mediated deacetylation (at K98, impairing γ-tubulin interaction and centrosomal localization), and modulates innate immune and LC3-associated phagocytic responses through interactions with GGPS1/RAC1 and the TRIM21-RUBCN axis, respectively."},"narrative":{"teleology":[{"year":2022,"claim":"Three simultaneous studies established ENKD1 as a centrosomal microtubule-associated protein with dual roles in ciliogenesis initiation and mitotic spindle orientation, answering the fundamental question of what ENKD1 does at the molecular level.","evidence":"In vitro tubulin polymerization, microtubule co-sedimentation, KO mice with epidermal and ciliary phenotypes, CP110/CEP97 competition Co-IP, double-knockdown epistasis, domain-rescue experiments, Hedgehog pathway reporters","pmids":["35301795","35197565","35072334"],"confidence":"High","gaps":["Structural basis of ENKD1 microtubule binding and CP110 competition not resolved","Whether ENKD1 ciliogenesis and spindle orientation roles are independently regulated is unknown","Hedgehog signaling dependence on ENKD1 not tested in vivo"]},{"year":2024,"claim":"Identification of CYLD-mediated deubiquitination at K141 and K242 revealed the first post-translational regulatory mechanism controlling ENKD1 function, linking it to Ezrin localization and retinal phagocytosis.","evidence":"Co-IP, ubiquitination site mutagenesis, CYLD KO mice with retinal phenotype, Ezrin localization imaging in RPE cells","pmids":["39373352"],"confidence":"High","gaps":["The E3 ligase responsible for ENKD1 ubiquitination at K141/K242 is unidentified","Whether ENKD1-Ezrin interaction is direct or scaffolded is unresolved","How deubiquitination at these sites specifically alters ENKD1 conformation or partner binding is unknown"]},{"year":2025,"claim":"Discovery that HDAC6 deacetylates ENKD1 at K98 to impair γ-tubulin interaction established a second post-translational switch controlling ENKD1 centrosomal targeting and spindle orientation.","evidence":"K98 acetylation-site mutagenesis, Co-IP of ENKD1–γ-tubulin, HDAC6 overexpression in mouse corneal epithelium, spindle orientation assays","pmids":["40155750"],"confidence":"High","gaps":["The acetyltransferase that acetylates ENKD1 at K98 is unknown","Whether acetylation and ubiquitination of ENKD1 are coordinated or independent is untested","Structural mechanism by which K98 acetylation modulates γ-tubulin binding is unresolved"]},{"year":2025,"claim":"Two studies expanded ENKD1's functional repertoire beyond the cytoskeleton into innate immunity, showing it suppresses TLR-driven inflammation via GGPS1/RAC1 and limits LC3-associated phagocytosis via TRIM21-mediated RUBCN degradation.","evidence":"GGPS1 enzymatic activity assays, RAC1 activation assays, ENKD1 KO macrophages with enhanced LAP, K48-linked ubiquitination assays on RUBCN, in vivo sepsis and bacterial infection models in KO mice","pmids":["40048432","41187080"],"confidence":"High","gaps":["Whether ENKD1's immune functions depend on its centrosomal/microtubule localization is unknown","How ENKD1 is transcriptionally or post-translationally regulated in immune cells specifically is uncharacterized","Whether GGPS1 modulation and TRIM21-RUBCN degradation occur in the same cell types or are tissue-specific is untested"]},{"year":2025,"claim":"ENKD1 was shown to enhance microtubule stability partly through EB1 in keratinocytes, linking its cytoskeletal role to cell migration and tissue mechanics.","evidence":"Enkd1 KO mice with reduced epidermal elasticity, microtubule stability and keratinocyte migration assays, EB1 interaction analysis","pmids":["40879264"],"confidence":"Medium","gaps":["The ENKD1-EB1 interaction is not fully characterized biochemically","Whether EB1 mediates ENKD1's microtubule-stabilizing activity at centrosomes versus the lattice is unclear","Mechanistic basis of reduced epidermal elasticity upon ENKD1 loss is not defined"]},{"year":null,"claim":"It remains unknown how ENKD1's cytoskeletal and immune-regulatory functions are coordinated, whether tissue-specific post-translational modifications partition these roles, and what the structural basis of ENKD1's interactions with its diverse partners is.","evidence":"","pmids":[],"confidence":"High","gaps":["No structural model of ENKD1 or any of its interaction interfaces exists","Interplay between acetylation, ubiquitination, and partner selection is uncharacterized","Whether ENKD1 immune functions are relevant in non-myeloid cells is unknown"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[1,2,7]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0,5,6]}],"localization":[{"term_id":"GO:0005815","term_label":"microtubule organizing center","supporting_discovery_ids":[0,1,4,7]},{"term_id":"GO:0005856","term_label":"cytoskeleton","supporting_discovery_ids":[1,2,7]},{"term_id":"GO:0005929","term_label":"cilium","supporting_discovery_ids":[0,2]}],"pathway":[{"term_id":"R-HSA-1852241","term_label":"Organelle biogenesis and maintenance","supporting_discovery_ids":[0,2]},{"term_id":"R-HSA-1640170","term_label":"Cell Cycle","supporting_discovery_ids":[1,4]},{"term_id":"R-HSA-168256","term_label":"Immune System","supporting_discovery_ids":[5,6]}],"complexes":[],"partners":["CP110","CEP97","CYLD","HDAC6","GGPS1","TRIM21","RUBCN","EB1"],"other_free_text":[]},"mechanistic_narrative":"ENKD1 is a centrosomal microtubule-associated protein that stabilizes microtubules and orchestrates diverse cellular processes including ciliogenesis, mitotic spindle orientation, and innate immune regulation. ENKD1 promotes tubulin polymerization and microtubule stability at centrioles and astral arrays, orienting the mitotic spindle in epithelia; it also initiates ciliogenesis by competing with CEP97 for CP110 binding, displacing CP110 from the mother centriole [PMID:35301795, PMID:35197565, PMID:35072334]. ENKD1 centrosomal localization and function are regulated post-translationally: acetylation at K98 by HDAC6 impairs γ-tubulin interaction and centrosomal targeting, while CYLD-mediated deubiquitination at K141/K242 enables ENKD1 to promote Ezrin microvillar localization required for retinal pigment epithelium phagocytosis [PMID:40155750, PMID:39373352]. Beyond cytoskeletal roles, ENKD1 suppresses innate immune activation by binding GGPS1 to reduce geranylgeranylation-dependent RAC1 signaling downstream of TLR activation, and recruits TRIM21 to ubiquitinate and degrade RUBCN, thereby limiting LC3-associated phagocytosis [PMID:40048432, PMID:41187080]."},"prefetch_data":{"uniprot":{"accession":"Q9H0I2","full_name":"Enkurin domain-containing protein 1","aliases":[],"length_aa":346,"mass_kda":38.8,"function":"Microtubule-binding protein which regulates microtubule organization and stability (PubMed:35072334, PubMed:35197565). Promotes the stability of astral microtubules and facilitates the proper orientation of the mitotic spindle (PubMed:35197565). This allows the oriented division of basal keratinocytes and contributes to epidermal stratification (By similarity). Required for the assembly of both primary and motile cilia (PubMed:35301795). Destabilizes the interaction between CCP110 and CEP97 by competing with CEP97 for binding to CCP110 which promotes the removal of CCP110 and CEP97 from the mother centriole and allows the initiation of ciliogenesis (PubMed:35301795)","subcellular_location":"Cytoplasm, cytoskeleton, microtubule organizing center, centrosome; Cytoplasm, cytoskeleton, microtubule organizing center, centrosome, centriole; Cytoplasm, cytoskeleton, cilium basal body; Cell projection, cilium; Cytoplasm, cytoskeleton, spindle; Cytoplasm, cytoskeleton, spindle pole; Cytoplasm, cytoskeleton, cilium axoneme","url":"https://www.uniprot.org/uniprotkb/Q9H0I2/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/ENKD1","classification":"Not Classified","n_dependent_lines":39,"n_total_lines":1208,"dependency_fraction":0.03228476821192053},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/ENKD1","total_profiled":1310},"omim":[{"mim_id":"621119","title":"ENKURIN DOMAIN-CONTAINING PROTEIN 1; ENKD1","url":"https://www.omim.org/entry/621119"},{"mim_id":"605018","title":"CYLD LYSINE-63 DEUBIQUITINASE; CYLD","url":"https://www.omim.org/entry/605018"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Supported","locations":[{"location":"Plasma membrane","reliability":"Supported"},{"location":"Centrosome","reliability":"Supported"},{"location":"Basal body","reliability":"Supported"},{"location":"Primary cilium","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/ENKD1"},"hgnc":{"alias_symbol":["DKFZP434A1319","FBB11"],"prev_symbol":["C16orf48"]},"alphafold":{"accession":"Q9H0I2","domains":[{"cath_id":"1.10.287","chopping":"288-344","consensus_level":"high","plddt":94.3098,"start":288,"end":344}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9H0I2","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9H0I2-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9H0I2-F1-predicted_aligned_error_v6.png","plddt_mean":76.25},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=ENKD1","jax_strain_url":"https://www.jax.org/strain/search?query=ENKD1"},"sequence":{"accession":"Q9H0I2","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9H0I2.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9H0I2/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9H0I2"}},"corpus_meta":[{"pmid":"35301795","id":"PMC_35301795","title":"ENKD1 promotes CP110 removal through competing with CEP97 to initiate ciliogenesis.","date":"2022","source":"EMBO reports","url":"https://pubmed.ncbi.nlm.nih.gov/35301795","citation_count":26,"is_preprint":false},{"pmid":"35197565","id":"PMC_35197565","title":"ENKD1 promotes epidermal stratification by regulating spindle orientation in basal keratinocytes.","date":"2022","source":"Cell death and differentiation","url":"https://pubmed.ncbi.nlm.nih.gov/35197565","citation_count":24,"is_preprint":false},{"pmid":"35072334","id":"PMC_35072334","title":"ENKD1 is a centrosomal and ciliary microtubule-associated protein important for primary cilium content regulation.","date":"2022","source":"The FEBS journal","url":"https://pubmed.ncbi.nlm.nih.gov/35072334","citation_count":9,"is_preprint":false},{"pmid":"33724673","id":"PMC_33724673","title":"Enkurin domain containing 1 (ENKD1) regulates the proliferation, migration and invasion of non-small cell lung cancer cells.","date":"2021","source":"Asia-Pacific journal of clinical oncology","url":"https://pubmed.ncbi.nlm.nih.gov/33724673","citation_count":8,"is_preprint":false},{"pmid":"39373352","id":"PMC_39373352","title":"CYLD Maintains Retinal Homeostasis by Deubiquitinating ENKD1 and Promoting the Phagocytosis of Photoreceptor Outer Segments.","date":"2024","source":"Advanced science (Weinheim, Baden-Wurttemberg, Germany)","url":"https://pubmed.ncbi.nlm.nih.gov/39373352","citation_count":7,"is_preprint":false},{"pmid":"36960713","id":"PMC_36960713","title":"Upregulation of ENKD1 disrupts cellular homeostasis to promote lymphoma development.","date":"2023","source":"Journal of cellular physiology","url":"https://pubmed.ncbi.nlm.nih.gov/36960713","citation_count":2,"is_preprint":false},{"pmid":"40048432","id":"PMC_40048432","title":"ENKD1 modulates innate immune responses through enhanced geranylgeranyl pyrophosphate synthase activity.","date":"2025","source":"Cell reports","url":"https://pubmed.ncbi.nlm.nih.gov/40048432","citation_count":2,"is_preprint":false},{"pmid":"40155750","id":"PMC_40155750","title":"HDAC6 deacetylates ENKD1 to regulate mitotic spindle behavior and corneal epithelial homeostasis.","date":"2025","source":"EMBO reports","url":"https://pubmed.ncbi.nlm.nih.gov/40155750","citation_count":1,"is_preprint":false},{"pmid":"40304823","id":"PMC_40304823","title":"MiR-760 protects against lipopolysaccharide-induced septic acute kidney injury by targeting ENKD1.","date":"2025","source":"Clinical and experimental nephrology","url":"https://pubmed.ncbi.nlm.nih.gov/40304823","citation_count":0,"is_preprint":false},{"pmid":"41187080","id":"PMC_41187080","title":"ENKD1 attenuates antibacterial immunity by facilitating TRIM21-mediated RUBCN degradation to suppress LC3-associated phagocytosis.","date":"2025","source":"Proceedings of the National Academy of Sciences of the United States of America","url":"https://pubmed.ncbi.nlm.nih.gov/41187080","citation_count":0,"is_preprint":false},{"pmid":"40879264","id":"PMC_40879264","title":"ENKD1 Modulates Skin Elasticity Through Microtubule Stability Regulation.","date":"2025","source":"Cytoskeleton (Hoboken, N.J.)","url":"https://pubmed.ncbi.nlm.nih.gov/40879264","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":6059,"output_tokens":2287,"usd":0.026241},"stage2":{"model":"claude-opus-4-6","input_tokens":5581,"output_tokens":2165,"usd":0.123045},"total_usd":0.149286,"stage1_batch_id":"msgbatch_0118RScg3WGaGkaZRtWZbtce","stage2_batch_id":"msgbatch_01Cpfzvtbj42aqp5oYZ5Te2s","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2022,\n      \"finding\": \"ENKD1 localizes to the centrosome throughout ciliogenesis and competes with CEP97 for binding to CP110, thereby displacing CP110 from the mother centriole to initiate ciliogenesis. ENKD1 depletion enhances the CP110-CEP97 interaction and retains CP110 at the mother centriole, blocking cilium formation. Simultaneous knockdown of ENKD1 and CP110 rescues ciliogenesis defects caused by ENKD1 depletion.\",\n      \"method\": \"Knockout mice, super-resolution microscopy, protein interaction/competition assays (Co-IP), double knockdown epistasis, cellular ciliogenesis assays\",\n      \"journal\": \"EMBO reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal protein interaction, epistasis with double KD, KO mouse phenotype, multiple orthogonal methods\",\n      \"pmids\": [\"35301795\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"ENKD1 is a microtubule-binding protein that stabilizes astral microtubules to orient the mitotic spindle in basal keratinocytes. ENKD1 depletion impairs spindle orientation and delays mitotic progression; re-introduction of the ENKD1 microtubule-binding domain rescues spindle orientation defects. Loss of ENKD1 in mice leads to thinner epidermis due to reduced asymmetric division of basal keratinocytes.\",\n      \"method\": \"Knockout mice, domain-rescue experiments, microtubule co-sedimentation/binding assays, live-cell imaging of spindle orientation, mitosis timing assays\",\n      \"journal\": \"Cell death and differentiation\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — microtubule-binding assay, domain rescue, KO mouse phenotype, multiple orthogonal methods\",\n      \"pmids\": [\"35197565\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"ENKD1 is a MAP component of the centriole wall and ciliary axoneme. In vitro and cellular assays show ENKD1 promotes tubulin polymerization and microtubule stability; ENKD1 overexpression disrupts microtubule organization, and ENKD1 depletion impairs ciliary length and content regulation and prevents Hedgehog pathway activation in response to stimulation.\",\n      \"method\": \"In vitro tubulin polymerization assay, cellular microtubule stability assays, proximity-interaction proteomics, siRNA knockdown with ciliary length/content measurement, Hedgehog pathway reporter assays\",\n      \"journal\": \"The FEBS journal\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — in vitro reconstitution of MAP activity, proximity interactome, multiple cellular assays\",\n      \"pmids\": [\"35072334\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"The deubiquitinase CYLD interacts with ENKD1 and deubiquitinates it at lysine residues K141 and K242. Deubiquitinated ENKD1 then interacts with Ezrin and promotes its microvillar localization in retinal pigment epithelium (RPE) cells, which is required for phagocytosis of photoreceptor outer segments. CYLD-deficient mice have abnormal retinal structure and impaired phagocytic function.\",\n      \"method\": \"Co-IP, ubiquitination assays with site-directed mutagenesis (K141, K242), CYLD knockout mice, retinal phenotype analysis, Ezrin localization imaging\",\n      \"journal\": \"Advanced science (Weinheim, Baden-Wurttemberg, Germany)\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — mutagenesis of ubiquitination sites, KO mouse phenotype, reciprocal Co-IP, multiple orthogonal methods\",\n      \"pmids\": [\"39373352\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"HDAC6 deacetylates ENKD1 at lysine 98, which impairs ENKD1's interaction with γ-tubulin and restrains ENKD1's centrosomal localization, thereby disrupting mitotic spindle orientation and positioning in corneal epithelial cells.\",\n      \"method\": \"Acetylation site mutagenesis (K98), Co-IP, HDAC6 overexpression in mice, centrosomal localization imaging, spindle orientation assays\",\n      \"journal\": \"EMBO reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — site-specific mutagenesis, Co-IP of ENKD1-γ-tubulin interaction, in vivo mouse model, multiple methods\",\n      \"pmids\": [\"40155750\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"ENKD1 interacts with geranylgeranyl diphosphate synthase 1 (GGPS1) and modulates its enzymatic activity, reducing geranylgeranyl diphosphate production, which leads to RAC1 inactivation and suppression of pro-inflammatory signaling downstream of TLR activation. ENKD1 deletion enhances innate immune activation and exacerbates septic inflammation.\",\n      \"method\": \"Co-IP, GGPS1 enzymatic activity assay, ENKD1 knockout cells/mice, RAC1 activation assay, TLR signaling assays\",\n      \"journal\": \"Cell reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — enzymatic activity modulation assay, KO mouse phenotype, Co-IP, RAC1 activity measurement\",\n      \"pmids\": [\"40048432\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"ENKD1 interacts with the E3 ubiquitin ligase TRIM21, which mediates K48-linked polyubiquitination and degradation of RUBCN (Run domain Beclin-1-interacting and cysteine-rich domain-containing protein), thereby dampening RUBCN's role in LC3-associated phagocytosis (LAP). ENKD1-deficient macrophages show enhanced LAP, increased ROS, and improved phagosome-lysosome fusion, while ENKD1-deficient mice show improved bacterial clearance.\",\n      \"method\": \"Co-IP, ubiquitination assay (K48-linked), ENKD1 KO macrophages, in vivo bacterial infection models, LC3 lipidation assays, phagosome-lysosome fusion assays\",\n      \"journal\": \"Proceedings of the National Academy of Sciences of the United States of America\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1–2 — ubiquitination linkage assay, KO mouse in vivo model, multiple mechanistic assays, reciprocal Co-IP\",\n      \"pmids\": [\"41187080\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"ENKD1 localizes to centrosomes and microtubules in basal keratinocytes and enhances microtubule stability, at least in part through EB1. Loss of ENKD1 destabilizes microtubules, impedes keratinocyte migration, and reduces epidermal elasticity in knockout mice.\",\n      \"method\": \"Enkd1 knockout mice, microtubule stability assays, keratinocyte migration assays, localization imaging, EB1 interaction analysis\",\n      \"journal\": \"Cytoskeleton (Hoboken, N.J.)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2–3 — KO mouse phenotype, microtubule stability assay, EB1 interaction suggested but not fully characterized\",\n      \"pmids\": [\"40879264\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"ENKD1 is a centrosomal microtubule-associated protein that stabilizes astral and centriolar microtubules, regulates ciliogenesis by competing with CEP97 to displace CP110 from the mother centriole, orients the mitotic spindle via astral microtubule stabilization, is subject to post-translational regulation by CYLD-mediated deubiquitination (at K141/K242, promoting Ezrin localization) and HDAC6-mediated deacetylation (at K98, impairing γ-tubulin interaction and centrosomal localization), and modulates innate immune and LC3-associated phagocytic responses through interactions with GGPS1/RAC1 and the TRIM21-RUBCN axis, respectively.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"ENKD1 is a centrosomal microtubule-associated protein that stabilizes microtubules and orchestrates diverse cellular processes including ciliogenesis, mitotic spindle orientation, and innate immune regulation. ENKD1 promotes tubulin polymerization and microtubule stability at centrioles and astral arrays, orienting the mitotic spindle in epithelia; it also initiates ciliogenesis by competing with CEP97 for CP110 binding, displacing CP110 from the mother centriole [PMID:35301795, PMID:35197565, PMID:35072334]. ENKD1 centrosomal localization and function are regulated post-translationally: acetylation at K98 by HDAC6 impairs γ-tubulin interaction and centrosomal targeting, while CYLD-mediated deubiquitination at K141/K242 enables ENKD1 to promote Ezrin microvillar localization required for retinal pigment epithelium phagocytosis [PMID:40155750, PMID:39373352]. Beyond cytoskeletal roles, ENKD1 suppresses innate immune activation by binding GGPS1 to reduce geranylgeranylation-dependent RAC1 signaling downstream of TLR activation, and recruits TRIM21 to ubiquitinate and degrade RUBCN, thereby limiting LC3-associated phagocytosis [PMID:40048432, PMID:41187080].\",\n  \"teleology\": [\n    {\n      \"year\": 2022,\n      \"claim\": \"Three simultaneous studies established ENKD1 as a centrosomal microtubule-associated protein with dual roles in ciliogenesis initiation and mitotic spindle orientation, answering the fundamental question of what ENKD1 does at the molecular level.\",\n      \"evidence\": \"In vitro tubulin polymerization, microtubule co-sedimentation, KO mice with epidermal and ciliary phenotypes, CP110/CEP97 competition Co-IP, double-knockdown epistasis, domain-rescue experiments, Hedgehog pathway reporters\",\n      \"pmids\": [\"35301795\", \"35197565\", \"35072334\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Structural basis of ENKD1 microtubule binding and CP110 competition not resolved\",\n        \"Whether ENKD1 ciliogenesis and spindle orientation roles are independently regulated is unknown\",\n        \"Hedgehog signaling dependence on ENKD1 not tested in vivo\"\n      ]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Identification of CYLD-mediated deubiquitination at K141 and K242 revealed the first post-translational regulatory mechanism controlling ENKD1 function, linking it to Ezrin localization and retinal phagocytosis.\",\n      \"evidence\": \"Co-IP, ubiquitination site mutagenesis, CYLD KO mice with retinal phenotype, Ezrin localization imaging in RPE cells\",\n      \"pmids\": [\"39373352\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"The E3 ligase responsible for ENKD1 ubiquitination at K141/K242 is unidentified\",\n        \"Whether ENKD1-Ezrin interaction is direct or scaffolded is unresolved\",\n        \"How deubiquitination at these sites specifically alters ENKD1 conformation or partner binding is unknown\"\n      ]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Discovery that HDAC6 deacetylates ENKD1 at K98 to impair γ-tubulin interaction established a second post-translational switch controlling ENKD1 centrosomal targeting and spindle orientation.\",\n      \"evidence\": \"K98 acetylation-site mutagenesis, Co-IP of ENKD1–γ-tubulin, HDAC6 overexpression in mouse corneal epithelium, spindle orientation assays\",\n      \"pmids\": [\"40155750\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"The acetyltransferase that acetylates ENKD1 at K98 is unknown\",\n        \"Whether acetylation and ubiquitination of ENKD1 are coordinated or independent is untested\",\n        \"Structural mechanism by which K98 acetylation modulates γ-tubulin binding is unresolved\"\n      ]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Two studies expanded ENKD1's functional repertoire beyond the cytoskeleton into innate immunity, showing it suppresses TLR-driven inflammation via GGPS1/RAC1 and limits LC3-associated phagocytosis via TRIM21-mediated RUBCN degradation.\",\n      \"evidence\": \"GGPS1 enzymatic activity assays, RAC1 activation assays, ENKD1 KO macrophages with enhanced LAP, K48-linked ubiquitination assays on RUBCN, in vivo sepsis and bacterial infection models in KO mice\",\n      \"pmids\": [\"40048432\", \"41187080\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"Whether ENKD1's immune functions depend on its centrosomal/microtubule localization is unknown\",\n        \"How ENKD1 is transcriptionally or post-translationally regulated in immune cells specifically is uncharacterized\",\n        \"Whether GGPS1 modulation and TRIM21-RUBCN degradation occur in the same cell types or are tissue-specific is untested\"\n      ]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"ENKD1 was shown to enhance microtubule stability partly through EB1 in keratinocytes, linking its cytoskeletal role to cell migration and tissue mechanics.\",\n      \"evidence\": \"Enkd1 KO mice with reduced epidermal elasticity, microtubule stability and keratinocyte migration assays, EB1 interaction analysis\",\n      \"pmids\": [\"40879264\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"The ENKD1-EB1 interaction is not fully characterized biochemically\",\n        \"Whether EB1 mediates ENKD1's microtubule-stabilizing activity at centrosomes versus the lattice is unclear\",\n        \"Mechanistic basis of reduced epidermal elasticity upon ENKD1 loss is not defined\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"It remains unknown how ENKD1's cytoskeletal and immune-regulatory functions are coordinated, whether tissue-specific post-translational modifications partition these roles, and what the structural basis of ENKD1's interactions with its diverse partners is.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\n        \"No structural model of ENKD1 or any of its interaction interfaces exists\",\n        \"Interplay between acetylation, ubiquitination, and partner selection is uncharacterized\",\n        \"Whether ENKD1 immune functions are relevant in non-myeloid cells is unknown\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [1, 2, 7]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0, 5, 6]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005815\", \"supporting_discovery_ids\": [0, 1, 4, 7]},\n      {\"term_id\": \"GO:0005856\", \"supporting_discovery_ids\": [1, 2, 7]},\n      {\"term_id\": \"GO:0005929\", \"supporting_discovery_ids\": [0, 2]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"GO:0005929\", \"supporting_discovery_ids\": []},\n      {\"term_id\": \"R-HSA-1852241\", \"supporting_discovery_ids\": [0, 2]},\n      {\"term_id\": \"R-HSA-1640170\", \"supporting_discovery_ids\": [1, 4]},\n      {\"term_id\": \"R-HSA-168256\", \"supporting_discovery_ids\": [5, 6]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"CP110\", \"CEP97\", \"CYLD\", \"HDAC6\", \"GGPS1\", \"TRIM21\", \"RUBCN\", \"EB1\"],\n    \"other_free_text\": []\n  }\n}\n```"}