{"gene":"NPHP4","run_date":"2026-06-10T05:19:52","timeline":{"discoveries":[{"year":2011,"finding":"NPHP4 directly interacts with the kinase LATS1 and inhibits LATS1-mediated phosphorylation of YAP and TAZ, leading to their release from 14-3-3 binding and nuclear translocation, thereby promoting TEAD/TAZ/YAP-dependent transcriptional activity. NPHP4 thus acts as a negative regulator of mammalian Hippo signaling and promotes cell proliferation through this mechanism.","method":"Co-immunoprecipitation, phosphorylation assays, nuclear translocation assays, knockdown with TEAD/TAZ reporter assays, proliferation assays","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 / Moderate — reciprocal Co-IP, in vitro phosphorylation assay, multiple orthogonal functional readouts (nuclear translocation, transcriptional reporter, proliferation), single lab","pmids":["21555462"],"is_preprint":false},{"year":2014,"finding":"NPHP4 is stably incorporated into the distal part of the flagellar transition zone (close to the membrane, distal to CEP290) in Chlamydomonas reinhardtii, and functions as an essential component of a barrier that regulates both membrane protein composition and exclusion of large soluble proteins (>50 kDa) from flagella. Loss of NPHP4 results in reduced membrane proteins and entry of cellular housekeeping proteins into flagella.","method":"Biochemical fractionation of isolated flagella from nphp4-null vs. wild-type Chlamydomonas, immunofluorescence localization, ultrastructural analysis","journal":"Journal of cell science","confidence":"High","confidence_rationale":"Tier 2 / Strong — null mutant with direct biochemical comparison of flagellar fractions, localization experiment with functional consequence, replicated across multiple protein classes","pmids":["25150219"],"is_preprint":false},{"year":2015,"finding":"NPHP4 interacts with the polarity protein Inturned (via co-immunoprecipitation), and Inturned mediates formation of a ternary complex between NPHP4 and the actin nucleator DAAM1. NPHP4 depletion in Xenopus multiciliated cells disrupts the subapical actin layer required for cilia polarization and directional fluid flow. NPHP4 depletion also prevents association of Inturned with basal bodies.","method":"Co-immunoprecipitation, morpholino knockdown in Xenopus laevis epidermis, immunofluorescence imaging of subapical actin and basal bodies, ciliary beat and fluid flow assays","journal":"The Journal of cell biology","confidence":"High","confidence_rationale":"Tier 2 / Moderate — co-IP demonstrating ternary complex, knockdown with defined structural and functional phenotypes, multiple orthogonal methods in single study","pmids":["26644512"],"is_preprint":false},{"year":2010,"finding":"NPHP4 localizes to the transition zone of the connecting cilia in photoreceptors. Loss of NPHP4 (nonsense mutation in Nphp4) causes failure of photoreceptor outer segment formation with mislocalization of outer segment markers to inner segments and outer nuclear layer, rapid synaptic ribbon degeneration, and male infertility with reduced sperm motility, without structural defects in connecting cilia.","method":"Immunofluorescence localization, ERG recording, electron microscopy of photoreceptor structure, sperm motility/count analysis in Nphp4-nmf192 mouse mutant","journal":"Human molecular genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — defined KO mouse with multiple phenotypic readouts and localization, single lab","pmids":["21078623"],"is_preprint":false},{"year":2012,"finding":"RPGRIP1 is required for the ciliary targeting of NPHP4 (and RPGR, SDCCAG8) specifically in photoreceptors: loss of RPGRIP1 expression in Rpgrip1(nmf247) mice abolishes NPHP4 and RPGR from photoreceptor cilia and shifts NPHP4 and SDCCAG8 to an ER-associated membrane fraction, while ciliary localization of these proteins is unaffected in kidney cells of the same mutant.","method":"Immunofluorescence and subcellular fractionation in Rpgrip1(nmf247) mouse retina and kidney, immunolocalization of NPHP4 relative to centrin-2 and acetylated-α-tubulin","journal":"Cell death & disease","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — cell fractionation combined with immunofluorescence in defined mutant mouse, cell-type-specific comparisons, single lab","pmids":["22825473"],"is_preprint":false},{"year":2012,"finding":"Knockdown of nphp4 in zebrafish disrupts formation and function of motile cilia in Kupffer's vesicle, impairing asymmetric fluid flow and left-right patterning. This L-R axis defect was partially rescued by wild-type human NPHP4 mRNA but not by patient-derived mutant NPHP4.","method":"Antisense morpholino knockdown in zebrafish, analysis of Kupffer's vesicle cilia, heart and gut laterality assays, rescue experiments with wild-type and mutant human NPHP4 mRNA","journal":"Circulation research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — morpholino KD with defined phenotype and human mRNA rescue/allele validation, single lab","pmids":["22550138"],"is_preprint":false},{"year":2005,"finding":"C. elegans NPHP-1 and NPHP-4 proteins co-localize to ciliated sensory endings and to male-specific sensory cilia. Single nphp-1 or nphp-4 mutants have intact cilia, but nphp-1; nphp-4 double mutants show male mating response defects, indicating redundant roles in ciliary sensory signal transduction.","method":"GFP fusion protein localization, behavioral assays in single and double nphp-1; nphp-4 C. elegans mutants, genetic epistasis","journal":"Experimental cell research","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis with defined behavioral readout, GFP localization, single lab","pmids":["15817158"],"is_preprint":false},{"year":2010,"finding":"In C. elegans, mks-1 and mks-3 genetically interact with a pathway involving nphp-1 and nphp-4 to influence proper positioning, orientation, and formation of cilia. Combined disruption of nphp and mks pathways has cell non-autonomous effects on C. elegans sensilla, demonstrating that nphp-4 functions in a pathway parallel to the MKS complex genes.","method":"Genetic epistasis analysis in C. elegans double and triple mutants, ciliogenesis and chemoreception assays, fluorescence imaging of MKS-3 localization","journal":"Journal of the American Society of Nephrology","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — genetic epistasis across multiple pathway mutants with defined ciliary phenotypes, single lab","pmids":["20150540"],"is_preprint":false},{"year":2016,"finding":"NPHP-4 in C. elegans influences the localization and function of the distal ciliary kinesin OSM-3: an OSM-3(S316F) phosphorylation-site mutation causes reduced IFT velocity and exacerbates nphp-4 ciliary defects (distal segment loss, dye-filling, osmotic avoidance defects) without affecting wild-type animals. FRAP analysis revealed that nphp-4 mutant background decreases OSM-3 cilia entry rate.","method":"Genetic screen, double mutant analysis, FRAP, GFP-tagged IFT velocity measurement, dye-filling and osmotic avoidance behavioral assays in C. elegans","journal":"PLoS genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — multiple orthogonal methods (FRAP, IFT velocity, behavioral assays, genetic epistasis), single lab","pmids":["26863025"],"is_preprint":false},{"year":2022,"finding":"Genetic interaction between nphp-4 and bbs-5 is evolutionarily conserved: nphp-4; bbs-5 double mutants in C. elegans exhibit phenotypes not seen in either single mutant; in mice, Nphp4; Bbs5 double mutants show reduced viability (fewer than expected with three mutant alleles), and postnatal conditional loss of Bbs5 compromised survival when combined with Nphp4 allele, indicating synergistic disruption of ciliary signaling.","method":"Mutagenesis screen in C. elegans, double mutant analysis in C. elegans/zebrafish/mouse, conditional allele in mouse, viability/phenotype scoring","journal":"Genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — evolutionarily conserved genetic interaction confirmed in three organisms, multiple genetic approaches, single lab","pmids":["34850872"],"is_preprint":false},{"year":2008,"finding":"A 180-bp deletion in exon/intron 5 of canine NPHP4 causes exon skipping and a truncated protein that retains the NPHP1-binding domain but lacks the RPGRIP1-interacting domain, leading to cone-rod dystrophy without kidney disease. This establishes domain-specific functional requirements: the RPGRIP1-interacting domain is necessary for retinal function.","method":"RT-PCR demonstrating exon skipping, protein domain analysis, segregation analysis in wire-haired dachshund pedigrees","journal":"Genome research","confidence":"Low","confidence_rationale":"Tier 3 / Moderate — natural mutation with RT-PCR confirmation and domain mapping, but functional domain assignments inferred from deletion breakpoints rather than direct mutagenesis","pmids":["18687878"],"is_preprint":false},{"year":2026,"finding":"In medaka (Oryzias latipes), nphp4 is expressed in Sertoli cells of the spermatogonial niche. CRISPR/Cas9-mediated nphp4 deficiency causes age-dependent infertility with sperm motility defects, head abnormalities, mitochondrial damage, Sertoli cell apoptosis, and altered Sertoli cell functional markers leading to premature germ cell depletion—identifying nphp4 as a regulator of testicular niche homeostasis.","method":"In situ hybridization for localization, CRISPR/Cas9 knockout, sperm motility and morphology analysis, transmission electron microscopy, transcriptomic profiling","journal":"Reproduction (Cambridge, England)","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — CRISPR KO with multiple orthogonal phenotypic readouts (motility, EM, transcriptomics, cell apoptosis), single lab, preprint not indicated but 2026 publication","pmids":["41782365"],"is_preprint":false}],"current_model":"NPHP4 (nephrocystin-4) is a transition zone protein that functions as a ciliary gate controlling the selective entry and retention of membrane and soluble proteins in cilia; it negatively regulates Hippo signaling by binding LATS1 and inhibiting YAP/TAZ phosphorylation to promote their nuclear activity; it organizes the subapical actin network in multiciliated cells through an Inturned–DAAM1 complex; it is required for photoreceptor outer segment formation and male germ cell homeostasis; and it cooperates genetically with MKS-complex genes and the BBSome in cilia assembly and ciliopathy pathogenesis."},"narrative":{"mechanistic_narrative":"NPHP4 (nephrocystin-4) is a transition zone protein that builds and gates the cilium, controlling the selective composition of ciliary membrane and matrix proteins and supporting ciliary signaling across photoreceptors, motile cilia, and sensory cilia [PMID:25150219, PMID:21078623]. At the distal transition zone it functions as a diffusion barrier that retains ciliary membrane proteins while excluding large soluble housekeeping proteins from the flagellar compartment [PMID:25150219]. NPHP4 is required for photoreceptor outer segment formation and for male germ cell homeostasis, with loss causing outer-segment marker mislocalization, synaptic ribbon degeneration, and sperm motility defects [PMID:21078623, PMID:41782365]; its targeting to photoreceptor cilia depends on RPGRIP1 [PMID:22825473]. In multiciliated cells NPHP4 organizes the subapical actin network required for ciliary polarization and directional fluid flow by nucleating an Inturned–DAAM1 complex and recruiting Inturned to basal bodies [PMID:26644512], and it is required for motile-cilia-driven left-right patterning [PMID:22550138]. Separately, NPHP4 acts as a negative regulator of Hippo signaling: it binds the kinase LATS1 and inhibits LATS1-mediated phosphorylation of YAP and TAZ, freeing them from 14-3-3 for nuclear TEAD-dependent transcription and promoting proliferation [PMID:21555462]. Genetically, NPHP4 operates in a pathway parallel to MKS-complex genes and synergizes with the BBSome component BBS5 and the ciliary kinesin OSM-3 in cilia assembly and signaling [PMID:20150540, PMID:26863025, PMID:34850872].","teleology":[{"year":2005,"claim":"Established that NPHP4 localizes to ciliated sensory endings and acts redundantly with NPHP1 in ciliary sensory signaling, defining its baseline role at the cilium rather than in general cytoplasm.","evidence":"GFP localization and genetic epistasis of single vs. nphp-1; nphp-4 double mutants in C. elegans","pmids":["15817158"],"confidence":"Medium","gaps":["Did not define the molecular barrier function","Redundancy mechanism with NPHP1 not resolved at protein level"]},{"year":2008,"claim":"Mapped domain-specific requirements by showing a truncation retaining the NPHP1-binding domain but lacking the RPGRIP1-interacting domain causes cone-rod dystrophy without kidney disease, separating retinal and renal functional modules.","evidence":"RT-PCR exon-skipping analysis and pedigree segregation of a natural canine NPHP4 deletion","pmids":["18687878"],"confidence":"Low","gaps":["Domain assignments inferred from deletion breakpoints, not direct mutagenesis","No biochemical confirmation of lost RPGRIP1 binding"]},{"year":2010,"claim":"Demonstrated NPHP4 is essential for photoreceptor outer segment formation and male fertility in mammals, connecting transition-zone localization to tissue-level ciliary phenotypes.","evidence":"Localization, ERG, EM and sperm analysis in the Nphp4-nmf192 mouse mutant","pmids":["21078623"],"confidence":"Medium","gaps":["Mechanism of outer-segment marker mislocalization not defined","No structural defect in connecting cilia explained"]},{"year":2011,"claim":"Uncovered a non-ciliary signaling role by showing NPHP4 binds LATS1 and inhibits YAP/TAZ phosphorylation, positioning it as a negative regulator of Hippo signaling and driver of proliferation.","evidence":"Reciprocal Co-IP, in vitro phosphorylation, nuclear translocation, TEAD reporter and proliferation assays","pmids":["21555462"],"confidence":"High","gaps":["Link between ciliary and Hippo-regulatory roles unresolved","No structural basis for LATS1 inhibition"]},{"year":2012,"claim":"Identified RPGRIP1 as the ciliary-targeting factor for NPHP4 in photoreceptors, explaining cell-type-specific localization (retina vs. kidney).","evidence":"Immunofluorescence and subcellular fractionation in Rpgrip1-nmf247 mouse retina and kidney","pmids":["22825473"],"confidence":"Medium","gaps":["Targeting mechanism in non-retinal tissues not identified","Direct NPHP4–RPGRIP1 binding not biochemically resolved here"]},{"year":2012,"claim":"Showed NPHP4 is required for motile-cilia function and left-right axis determination, with patient mutations failing to rescue, validating disease-relevant alleles.","evidence":"Morpholino knockdown in zebrafish Kupffer's vesicle with human wild-type vs. mutant mRNA rescue","pmids":["22550138"],"confidence":"Medium","gaps":["Molecular mechanism within motile cilia not defined","Morpholino specificity limitations"]},{"year":2014,"claim":"Defined the core molecular function: NPHP4 forms a distal transition-zone barrier gating both membrane protein composition and exclusion of large soluble proteins from cilia.","evidence":"Biochemical fractionation of flagella from nphp4-null vs. wild-type Chlamydomonas with localization and ultrastructure","pmids":["25150219"],"confidence":"High","gaps":["Structural organization of the barrier not resolved","Partner proteins constituting the barrier not fully enumerated"]},{"year":2015,"claim":"Extended NPHP4 function beyond gating to actin cytoskeleton organization by showing it nucleates an Inturned–DAAM1 complex required for subapical actin and ciliary polarization.","evidence":"Co-IP and morpholino knockdown in Xenopus multiciliated cells with actin/basal body imaging and fluid-flow assays","pmids":["26644512"],"confidence":"High","gaps":["Whether actin role is separable from gating role unknown","Direct DAAM1 binding partner geometry not resolved"]},{"year":2016,"claim":"Linked NPHP4 to intraflagellar transport by showing it influences distal kinesin OSM-3 cilia entry rate, connecting the barrier to IFT-dependent ciliary maintenance.","evidence":"Genetic screen, FRAP, IFT velocity, and behavioral assays in C. elegans nphp-4 and OSM-3 mutants","pmids":["26863025"],"confidence":"Medium","gaps":["Direct NPHP4–OSM-3 interaction not demonstrated","Mechanism of reduced OSM-3 entry unresolved"]},{"year":2022,"claim":"Established an evolutionarily conserved genetic interaction with the BBSome component BBS5, indicating synergistic control of ciliary signaling across species.","evidence":"Double mutant analysis in C. elegans, zebrafish and mouse plus conditional Bbs5 allele with viability scoring","pmids":["34850872"],"confidence":"Medium","gaps":["Molecular basis of NPHP4–BBSome synergy unknown","No physical interaction demonstrated"]},{"year":2026,"claim":"Refined the male-fertility role by localizing nphp4 to Sertoli cells and showing it maintains the spermatogonial niche, with loss causing Sertoli apoptosis and germ cell depletion.","evidence":"In situ hybridization, CRISPR/Cas9 knockout, EM and transcriptomics in medaka","pmids":["41782365"],"confidence":"Medium","gaps":["Whether the niche role is ciliary or signaling-based unresolved","Mitochondrial damage mechanism undefined"]},{"year":null,"claim":"How NPHP4's ciliary gating, actin-organizing, and Hippo-regulatory activities are mechanistically integrated within a single protein remains unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of NPHP4 barrier assembly","Connection between cilium-based and Hippo-signaling roles unestablished","Substrate/recruitment hierarchy at the transition zone undefined"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0008092","term_label":"cytoskeletal protein binding","supporting_discovery_ids":[2]},{"term_id":"GO:0098772","term_label":"molecular function regulator activity","supporting_discovery_ids":[0]},{"term_id":"GO:0060090","term_label":"molecular adaptor activity","supporting_discovery_ids":[1,2]}],"localization":[{"term_id":"GO:0005929","term_label":"cilium","supporting_discovery_ids":[1,3]},{"term_id":"GO:0005815","term_label":"microtubule organizing center","supporting_discovery_ids":[2]}],"pathway":[{"term_id":"R-HSA-162582","term_label":"Signal Transduction","supporting_discovery_ids":[0]},{"term_id":"R-HSA-1852241","term_label":"Organelle biogenesis and maintenance","supporting_discovery_ids":[1,2]}],"complexes":["NPHP4-Inturned-DAAM1 complex","ciliary transition zone"],"partners":["LATS1","INTURNED","DAAM1","RPGRIP1","NPHP1"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"O75161","full_name":"Nephrocystin-4","aliases":["Nephroretinin"],"length_aa":1426,"mass_kda":157.6,"function":"Involved in the organization of apical junctions; the function is proposed to implicate a NPHP1-4-8 module (PubMed:19755384, PubMed:21565611). Does not seem to be strictly required for ciliogenesis (PubMed:21565611). Required for building functional cilia. Involved in the organization of the subapical actin network in multiciliated epithelial cells. Seems to recruit INT to basal bodies of motile cilia which subsequently interacts with actin-modifying proteins such as DAAM1 (By similarity). In cooperation with INVS may down-regulate the canonical Wnt pathway and promote the Wnt-PCP pathway by regulating expression and subcellular location of disheveled proteins. Stabilizes protein levels of JADE1 and promotes its translocation to the nucleus leading to cooperative inhibition of canonical Wnt signaling (PubMed:21498478, PubMed:22654112). Acts as a negative regulator of the hippo pathway by association with LATS1 and modifying LATS1-dependent phosphorylation and localization of WWTR1/TAZ (PubMed:21555462)","subcellular_location":"Cytoplasm, cytoskeleton, cilium basal body; Cytoplasm, cytoskeleton, microtubule organizing center, centrosome; Cell junction, tight junction; Nucleus","url":"https://www.uniprot.org/uniprotkb/O75161/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/NPHP4","classification":"Not Classified","n_dependent_lines":7,"n_total_lines":1208,"dependency_fraction":0.005794701986754967},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/NPHP4","total_profiled":1310},"omim":[{"mim_id":"614144","title":"B9 DOMAIN-CONTAINING PROTEIN 1; B9D1","url":"https://www.omim.org/entry/614144"},{"mim_id":"612013","title":"COILED-COIL AND C2 DOMAINS-CONTAINING PROTEIN 2A; CC2D2A","url":"https://www.omim.org/entry/612013"},{"mim_id":"611951","title":"B9 DOMAIN-CONTAINING PROTEIN 2; B9D2","url":"https://www.omim.org/entry/611951"},{"mim_id":"610937","title":"RPGRIP1-LIKE; RPGRIP1L","url":"https://www.omim.org/entry/610937"},{"mim_id":"609884","title":"TRANSMEMBRANE PROTEIN 67; TMEM67","url":"https://www.omim.org/entry/609884"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Nucleoplasm","reliability":"Approved"},{"location":"Nuclear bodies","reliability":"Additional"},{"location":"Vesicles","reliability":"Additional"},{"location":"Cytosol","reliability":"Additional"}],"tissue_specificity":"Low tissue specificity","tissue_distribution":"Detected in all","driving_tissues":[],"url":"https://www.proteinatlas.org/search/NPHP4"},"hgnc":{"alias_symbol":["SLSN4","KIAA0673","POC10"],"prev_symbol":[]},"alphafold":{"accession":"O75161","domains":[{"cath_id":"2.60.40.150","chopping":"12-234","consensus_level":"high","plddt":80.0189,"start":12,"end":234},{"cath_id":"2.60.40.150","chopping":"237-314_336-369_383-451","consensus_level":"high","plddt":75.5829,"start":237,"end":451},{"cath_id":"2.60.40.150","chopping":"596-794_812-831","consensus_level":"high","plddt":80.8568,"start":596,"end":831},{"cath_id":"2.60.40.10","chopping":"977-1073_1100-1127","consensus_level":"high","plddt":86.4558,"start":977,"end":1127},{"cath_id":"2.60.40.10","chopping":"1133-1153_1169-1231","consensus_level":"medium","plddt":80.6769,"start":1133,"end":1231},{"cath_id":"2.60.40.10","chopping":"1243-1327","consensus_level":"medium","plddt":88.5425,"start":1243,"end":1327},{"cath_id":"2.60.40.10","chopping":"1331-1426","consensus_level":"high","plddt":87.895,"start":1331,"end":1426}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/O75161","model_url":"https://alphafold.ebi.ac.uk/files/AF-O75161-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-O75161-F1-predicted_aligned_error_v6.png","plddt_mean":71.31},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=NPHP4","jax_strain_url":"https://www.jax.org/strain/search?query=NPHP4"},"sequence":{"accession":"O75161","fasta_url":"https://rest.uniprot.org/uniprotkb/O75161.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/O75161/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/O75161"}},"corpus_meta":[{"pmid":"21555462","id":"PMC_21555462","title":"NPHP4, a cilia-associated protein, negatively regulates the Hippo pathway.","date":"2011","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/21555462","citation_count":129,"is_preprint":false},{"pmid":"25150219","id":"PMC_25150219","title":"NPHP4 controls ciliary trafficking of membrane proteins and large soluble proteins at the transition zone.","date":"2014","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/25150219","citation_count":78,"is_preprint":false},{"pmid":"21078623","id":"PMC_21078623","title":"NPHP4 is necessary for normal photoreceptor ribbon synapse maintenance and outer segment formation, and for sperm development.","date":"2010","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/21078623","citation_count":75,"is_preprint":false},{"pmid":"18687878","id":"PMC_18687878","title":"A deletion in nephronophthisis 4 (NPHP4) is associated with recessive cone-rod dystrophy in standard wire-haired dachshund.","date":"2008","source":"Genome research","url":"https://pubmed.ncbi.nlm.nih.gov/18687878","citation_count":71,"is_preprint":false},{"pmid":"20150540","id":"PMC_20150540","title":"Normal ciliogenesis requires synergy between the cystic kidney disease genes MKS-3 and NPHP-4.","date":"2010","source":"Journal of the American Society of Nephrology : JASN","url":"https://pubmed.ncbi.nlm.nih.gov/20150540","citation_count":53,"is_preprint":false},{"pmid":"26644512","id":"PMC_26644512","title":"The polarity protein Inturned links NPHP4 to Daam1 to control the subapical actin network in multiciliated cells.","date":"2015","source":"The Journal of cell biology","url":"https://pubmed.ncbi.nlm.nih.gov/26644512","citation_count":49,"is_preprint":false},{"pmid":"15817158","id":"PMC_15817158","title":"Functional characterization of the C. elegans nephrocystins NPHP-1 and NPHP-4 and their role in cilia and male sensory behaviors.","date":"2005","source":"Experimental cell 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to cerebello-oculo-renal syndrome and male infertility.","date":"2013","source":"Clinical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/23574405","citation_count":19,"is_preprint":false},{"pmid":"17954299","id":"PMC_17954299","title":"Novel mutations in NPHP4 in a consanguineous family with histological findings of focal segmental glomerulosclerosis.","date":"2007","source":"American journal of kidney diseases : the official journal of the National Kidney Foundation","url":"https://pubmed.ncbi.nlm.nih.gov/17954299","citation_count":17,"is_preprint":false},{"pmid":"26863025","id":"PMC_26863025","title":"A Screen for Modifiers of Cilia Phenotypes Reveals Novel MKS Alleles and Uncovers a Specific Genetic Interaction between osm-3 and nphp-4.","date":"2016","source":"PLoS genetics","url":"https://pubmed.ncbi.nlm.nih.gov/26863025","citation_count":17,"is_preprint":false},{"pmid":"34850872","id":"PMC_34850872","title":"Evolutionarily conserved genetic interactions between nphp-4 and bbs-5 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and renal function in non-diabetic Japanese population: the Takahata study.","date":"2010","source":"Journal of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/20844548","citation_count":8,"is_preprint":false},{"pmid":"21546380","id":"PMC_21546380","title":"Assessing the pathogenic potential of human Nephronophthisis disease-associated NPHP-4 missense mutations in C. elegans.","date":"2011","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/21546380","citation_count":7,"is_preprint":false},{"pmid":"16131712","id":"PMC_16131712","title":"Effect of splice-site polymorphisms of the TMPRSS4, NPHP4 and ORCTL4 genes on their mRNA expression.","date":"2005","source":"Journal of genetics","url":"https://pubmed.ncbi.nlm.nih.gov/16131712","citation_count":6,"is_preprint":false},{"pmid":"37831349","id":"PMC_37831349","title":"A novel NPHP4 homozygous missense variant identified in infertile brothers with multiple morphological abnormalities of the sperm flagella.","date":"2023","source":"Journal of assisted reproduction and genetics","url":"https://pubmed.ncbi.nlm.nih.gov/37831349","citation_count":6,"is_preprint":false},{"pmid":"25818963","id":"PMC_25818963","title":"Diverse phenotypic expression of NPHP4 mutations in four siblings.","date":"2014","source":"The Turkish journal of pediatrics","url":"https://pubmed.ncbi.nlm.nih.gov/25818963","citation_count":3,"is_preprint":false},{"pmid":"36316773","id":"PMC_36316773","title":"One novel ACOT7-NPHP4 fusion gene identified in one patient with acute lymphoblastic leukemia: a case report.","date":"2022","source":"BMC medical genomics","url":"https://pubmed.ncbi.nlm.nih.gov/36316773","citation_count":2,"is_preprint":false},{"pmid":"38895833","id":"PMC_38895833","title":"Identification of a Novel Deletion Variant (c.2999_3005delTGTGTGT/p.Asn1000SerfsTer4) in NPHP4 Associated With Nephronophthisis-4.","date":"2024","source":"Journal of clinical laboratory analysis","url":"https://pubmed.ncbi.nlm.nih.gov/38895833","citation_count":2,"is_preprint":false},{"pmid":"42044428","id":"PMC_42044428","title":"Molecular Spectrum and Deep Phenotyping of a Turkish Joubert Syndrome Cohort, Including a Potential Candidate Gene, NPHP4.","date":"2025","source":"Turkish archives of pediatrics","url":"https://pubmed.ncbi.nlm.nih.gov/42044428","citation_count":0,"is_preprint":false},{"pmid":"41782365","id":"PMC_41782365","title":"nphp4 deficiency disrupts testicular homeostasis and impairs male fertility in medaka (Oryzias latipes).","date":"2026","source":"Reproduction (Cambridge, England)","url":"https://pubmed.ncbi.nlm.nih.gov/41782365","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":15534,"output_tokens":3357,"usd":0.048479,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":10845,"output_tokens":3546,"usd":0.071438,"stage2_stop_reason":"end_turn"},"total_usd":0.119917,"stage1_batch_id":"msgbatch_013a8chtv3AWyTqv4z4sEF4C","stage2_batch_id":"msgbatch_01AHsuW63vinsvuTgzmQ3n62","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2011,\n      \"finding\": \"NPHP4 directly interacts with the kinase LATS1 and inhibits LATS1-mediated phosphorylation of YAP and TAZ, leading to their release from 14-3-3 binding and nuclear translocation, thereby promoting TEAD/TAZ/YAP-dependent transcriptional activity. NPHP4 thus acts as a negative regulator of mammalian Hippo signaling and promotes cell proliferation through this mechanism.\",\n      \"method\": \"Co-immunoprecipitation, phosphorylation assays, nuclear translocation assays, knockdown with TEAD/TAZ reporter assays, proliferation assays\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal Co-IP, in vitro phosphorylation assay, multiple orthogonal functional readouts (nuclear translocation, transcriptional reporter, proliferation), single lab\",\n      \"pmids\": [\"21555462\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"NPHP4 is stably incorporated into the distal part of the flagellar transition zone (close to the membrane, distal to CEP290) in Chlamydomonas reinhardtii, and functions as an essential component of a barrier that regulates both membrane protein composition and exclusion of large soluble proteins (>50 kDa) from flagella. Loss of NPHP4 results in reduced membrane proteins and entry of cellular housekeeping proteins into flagella.\",\n      \"method\": \"Biochemical fractionation of isolated flagella from nphp4-null vs. wild-type Chlamydomonas, immunofluorescence localization, ultrastructural analysis\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Strong — null mutant with direct biochemical comparison of flagellar fractions, localization experiment with functional consequence, replicated across multiple protein classes\",\n      \"pmids\": [\"25150219\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"NPHP4 interacts with the polarity protein Inturned (via co-immunoprecipitation), and Inturned mediates formation of a ternary complex between NPHP4 and the actin nucleator DAAM1. NPHP4 depletion in Xenopus multiciliated cells disrupts the subapical actin layer required for cilia polarization and directional fluid flow. NPHP4 depletion also prevents association of Inturned with basal bodies.\",\n      \"method\": \"Co-immunoprecipitation, morpholino knockdown in Xenopus laevis epidermis, immunofluorescence imaging of subapical actin and basal bodies, ciliary beat and fluid flow assays\",\n      \"journal\": \"The Journal of cell biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — co-IP demonstrating ternary complex, knockdown with defined structural and functional phenotypes, multiple orthogonal methods in single study\",\n      \"pmids\": [\"26644512\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"NPHP4 localizes to the transition zone of the connecting cilia in photoreceptors. Loss of NPHP4 (nonsense mutation in Nphp4) causes failure of photoreceptor outer segment formation with mislocalization of outer segment markers to inner segments and outer nuclear layer, rapid synaptic ribbon degeneration, and male infertility with reduced sperm motility, without structural defects in connecting cilia.\",\n      \"method\": \"Immunofluorescence localization, ERG recording, electron microscopy of photoreceptor structure, sperm motility/count analysis in Nphp4-nmf192 mouse mutant\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — defined KO mouse with multiple phenotypic readouts and localization, single lab\",\n      \"pmids\": [\"21078623\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"RPGRIP1 is required for the ciliary targeting of NPHP4 (and RPGR, SDCCAG8) specifically in photoreceptors: loss of RPGRIP1 expression in Rpgrip1(nmf247) mice abolishes NPHP4 and RPGR from photoreceptor cilia and shifts NPHP4 and SDCCAG8 to an ER-associated membrane fraction, while ciliary localization of these proteins is unaffected in kidney cells of the same mutant.\",\n      \"method\": \"Immunofluorescence and subcellular fractionation in Rpgrip1(nmf247) mouse retina and kidney, immunolocalization of NPHP4 relative to centrin-2 and acetylated-α-tubulin\",\n      \"journal\": \"Cell death & disease\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — cell fractionation combined with immunofluorescence in defined mutant mouse, cell-type-specific comparisons, single lab\",\n      \"pmids\": [\"22825473\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2012,\n      \"finding\": \"Knockdown of nphp4 in zebrafish disrupts formation and function of motile cilia in Kupffer's vesicle, impairing asymmetric fluid flow and left-right patterning. This L-R axis defect was partially rescued by wild-type human NPHP4 mRNA but not by patient-derived mutant NPHP4.\",\n      \"method\": \"Antisense morpholino knockdown in zebrafish, analysis of Kupffer's vesicle cilia, heart and gut laterality assays, rescue experiments with wild-type and mutant human NPHP4 mRNA\",\n      \"journal\": \"Circulation research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — morpholino KD with defined phenotype and human mRNA rescue/allele validation, single lab\",\n      \"pmids\": [\"22550138\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2005,\n      \"finding\": \"C. elegans NPHP-1 and NPHP-4 proteins co-localize to ciliated sensory endings and to male-specific sensory cilia. Single nphp-1 or nphp-4 mutants have intact cilia, but nphp-1; nphp-4 double mutants show male mating response defects, indicating redundant roles in ciliary sensory signal transduction.\",\n      \"method\": \"GFP fusion protein localization, behavioral assays in single and double nphp-1; nphp-4 C. elegans mutants, genetic epistasis\",\n      \"journal\": \"Experimental cell research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis with defined behavioral readout, GFP localization, single lab\",\n      \"pmids\": [\"15817158\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2010,\n      \"finding\": \"In C. elegans, mks-1 and mks-3 genetically interact with a pathway involving nphp-1 and nphp-4 to influence proper positioning, orientation, and formation of cilia. Combined disruption of nphp and mks pathways has cell non-autonomous effects on C. elegans sensilla, demonstrating that nphp-4 functions in a pathway parallel to the MKS complex genes.\",\n      \"method\": \"Genetic epistasis analysis in C. elegans double and triple mutants, ciliogenesis and chemoreception assays, fluorescence imaging of MKS-3 localization\",\n      \"journal\": \"Journal of the American Society of Nephrology\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — genetic epistasis across multiple pathway mutants with defined ciliary phenotypes, single lab\",\n      \"pmids\": [\"20150540\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"NPHP-4 in C. elegans influences the localization and function of the distal ciliary kinesin OSM-3: an OSM-3(S316F) phosphorylation-site mutation causes reduced IFT velocity and exacerbates nphp-4 ciliary defects (distal segment loss, dye-filling, osmotic avoidance defects) without affecting wild-type animals. FRAP analysis revealed that nphp-4 mutant background decreases OSM-3 cilia entry rate.\",\n      \"method\": \"Genetic screen, double mutant analysis, FRAP, GFP-tagged IFT velocity measurement, dye-filling and osmotic avoidance behavioral assays in C. elegans\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — multiple orthogonal methods (FRAP, IFT velocity, behavioral assays, genetic epistasis), single lab\",\n      \"pmids\": [\"26863025\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Genetic interaction between nphp-4 and bbs-5 is evolutionarily conserved: nphp-4; bbs-5 double mutants in C. elegans exhibit phenotypes not seen in either single mutant; in mice, Nphp4; Bbs5 double mutants show reduced viability (fewer than expected with three mutant alleles), and postnatal conditional loss of Bbs5 compromised survival when combined with Nphp4 allele, indicating synergistic disruption of ciliary signaling.\",\n      \"method\": \"Mutagenesis screen in C. elegans, double mutant analysis in C. elegans/zebrafish/mouse, conditional allele in mouse, viability/phenotype scoring\",\n      \"journal\": \"Genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — evolutionarily conserved genetic interaction confirmed in three organisms, multiple genetic approaches, single lab\",\n      \"pmids\": [\"34850872\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2008,\n      \"finding\": \"A 180-bp deletion in exon/intron 5 of canine NPHP4 causes exon skipping and a truncated protein that retains the NPHP1-binding domain but lacks the RPGRIP1-interacting domain, leading to cone-rod dystrophy without kidney disease. This establishes domain-specific functional requirements: the RPGRIP1-interacting domain is necessary for retinal function.\",\n      \"method\": \"RT-PCR demonstrating exon skipping, protein domain analysis, segregation analysis in wire-haired dachshund pedigrees\",\n      \"journal\": \"Genome research\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Moderate — natural mutation with RT-PCR confirmation and domain mapping, but functional domain assignments inferred from deletion breakpoints rather than direct mutagenesis\",\n      \"pmids\": [\"18687878\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2026,\n      \"finding\": \"In medaka (Oryzias latipes), nphp4 is expressed in Sertoli cells of the spermatogonial niche. CRISPR/Cas9-mediated nphp4 deficiency causes age-dependent infertility with sperm motility defects, head abnormalities, mitochondrial damage, Sertoli cell apoptosis, and altered Sertoli cell functional markers leading to premature germ cell depletion—identifying nphp4 as a regulator of testicular niche homeostasis.\",\n      \"method\": \"In situ hybridization for localization, CRISPR/Cas9 knockout, sperm motility and morphology analysis, transmission electron microscopy, transcriptomic profiling\",\n      \"journal\": \"Reproduction (Cambridge, England)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — CRISPR KO with multiple orthogonal phenotypic readouts (motility, EM, transcriptomics, cell apoptosis), single lab, preprint not indicated but 2026 publication\",\n      \"pmids\": [\"41782365\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"NPHP4 (nephrocystin-4) is a transition zone protein that functions as a ciliary gate controlling the selective entry and retention of membrane and soluble proteins in cilia; it negatively regulates Hippo signaling by binding LATS1 and inhibiting YAP/TAZ phosphorylation to promote their nuclear activity; it organizes the subapical actin network in multiciliated cells through an Inturned–DAAM1 complex; it is required for photoreceptor outer segment formation and male germ cell homeostasis; and it cooperates genetically with MKS-complex genes and the BBSome in cilia assembly and ciliopathy pathogenesis.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"NPHP4 (nephrocystin-4) is a transition zone protein that builds and gates the cilium, controlling the selective composition of ciliary membrane and matrix proteins and supporting ciliary signaling across photoreceptors, motile cilia, and sensory cilia [#1, #3]. At the distal transition zone it functions as a diffusion barrier that retains ciliary membrane proteins while excluding large soluble housekeeping proteins from the flagellar compartment [#1]. NPHP4 is required for photoreceptor outer segment formation and for male germ cell homeostasis, with loss causing outer-segment marker mislocalization, synaptic ribbon degeneration, and sperm motility defects [#3, #11]; its targeting to photoreceptor cilia depends on RPGRIP1 [#4]. In multiciliated cells NPHP4 organizes the subapical actin network required for ciliary polarization and directional fluid flow by nucleating an Inturned–DAAM1 complex and recruiting Inturned to basal bodies [#2], and it is required for motile-cilia-driven left-right patterning [#5]. Separately, NPHP4 acts as a negative regulator of Hippo signaling: it binds the kinase LATS1 and inhibits LATS1-mediated phosphorylation of YAP and TAZ, freeing them from 14-3-3 for nuclear TEAD-dependent transcription and promoting proliferation [#0]. Genetically, NPHP4 operates in a pathway parallel to MKS-complex genes and synergizes with the BBSome component BBS5 and the ciliary kinesin OSM-3 in cilia assembly and signaling [#7, #8, #9].\",\n  \"teleology\": [\n    {\n      \"year\": 2005,\n      \"claim\": \"Established that NPHP4 localizes to ciliated sensory endings and acts redundantly with NPHP1 in ciliary sensory signaling, defining its baseline role at the cilium rather than in general cytoplasm.\",\n      \"evidence\": \"GFP localization and genetic epistasis of single vs. nphp-1; nphp-4 double mutants in C. elegans\",\n      \"pmids\": [\"15817158\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Did not define the molecular barrier function\", \"Redundancy mechanism with NPHP1 not resolved at protein level\"]\n    },\n    {\n      \"year\": 2008,\n      \"claim\": \"Mapped domain-specific requirements by showing a truncation retaining the NPHP1-binding domain but lacking the RPGRIP1-interacting domain causes cone-rod dystrophy without kidney disease, separating retinal and renal functional modules.\",\n      \"evidence\": \"RT-PCR exon-skipping analysis and pedigree segregation of a natural canine NPHP4 deletion\",\n      \"pmids\": [\"18687878\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Domain assignments inferred from deletion breakpoints, not direct mutagenesis\", \"No biochemical confirmation of lost RPGRIP1 binding\"]\n    },\n    {\n      \"year\": 2010,\n      \"claim\": \"Demonstrated NPHP4 is essential for photoreceptor outer segment formation and male fertility in mammals, connecting transition-zone localization to tissue-level ciliary phenotypes.\",\n      \"evidence\": \"Localization, ERG, EM and sperm analysis in the Nphp4-nmf192 mouse mutant\",\n      \"pmids\": [\"21078623\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism of outer-segment marker mislocalization not defined\", \"No structural defect in connecting cilia explained\"]\n    },\n    {\n      \"year\": 2011,\n      \"claim\": \"Uncovered a non-ciliary signaling role by showing NPHP4 binds LATS1 and inhibits YAP/TAZ phosphorylation, positioning it as a negative regulator of Hippo signaling and driver of proliferation.\",\n      \"evidence\": \"Reciprocal Co-IP, in vitro phosphorylation, nuclear translocation, TEAD reporter and proliferation assays\",\n      \"pmids\": [\"21555462\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Link between ciliary and Hippo-regulatory roles unresolved\", \"No structural basis for LATS1 inhibition\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Identified RPGRIP1 as the ciliary-targeting factor for NPHP4 in photoreceptors, explaining cell-type-specific localization (retina vs. kidney).\",\n      \"evidence\": \"Immunofluorescence and subcellular fractionation in Rpgrip1-nmf247 mouse retina and kidney\",\n      \"pmids\": [\"22825473\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Targeting mechanism in non-retinal tissues not identified\", \"Direct NPHP4–RPGRIP1 binding not biochemically resolved here\"]\n    },\n    {\n      \"year\": 2012,\n      \"claim\": \"Showed NPHP4 is required for motile-cilia function and left-right axis determination, with patient mutations failing to rescue, validating disease-relevant alleles.\",\n      \"evidence\": \"Morpholino knockdown in zebrafish Kupffer's vesicle with human wild-type vs. mutant mRNA rescue\",\n      \"pmids\": [\"22550138\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular mechanism within motile cilia not defined\", \"Morpholino specificity limitations\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Defined the core molecular function: NPHP4 forms a distal transition-zone barrier gating both membrane protein composition and exclusion of large soluble proteins from cilia.\",\n      \"evidence\": \"Biochemical fractionation of flagella from nphp4-null vs. wild-type Chlamydomonas with localization and ultrastructure\",\n      \"pmids\": [\"25150219\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural organization of the barrier not resolved\", \"Partner proteins constituting the barrier not fully enumerated\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Extended NPHP4 function beyond gating to actin cytoskeleton organization by showing it nucleates an Inturned–DAAM1 complex required for subapical actin and ciliary polarization.\",\n      \"evidence\": \"Co-IP and morpholino knockdown in Xenopus multiciliated cells with actin/basal body imaging and fluid-flow assays\",\n      \"pmids\": [\"26644512\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Whether actin role is separable from gating role unknown\", \"Direct DAAM1 binding partner geometry not resolved\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Linked NPHP4 to intraflagellar transport by showing it influences distal kinesin OSM-3 cilia entry rate, connecting the barrier to IFT-dependent ciliary maintenance.\",\n      \"evidence\": \"Genetic screen, FRAP, IFT velocity, and behavioral assays in C. elegans nphp-4 and OSM-3 mutants\",\n      \"pmids\": [\"26863025\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Direct NPHP4–OSM-3 interaction not demonstrated\", \"Mechanism of reduced OSM-3 entry unresolved\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Established an evolutionarily conserved genetic interaction with the BBSome component BBS5, indicating synergistic control of ciliary signaling across species.\",\n      \"evidence\": \"Double mutant analysis in C. elegans, zebrafish and mouse plus conditional Bbs5 allele with viability scoring\",\n      \"pmids\": [\"34850872\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Molecular basis of NPHP4–BBSome synergy unknown\", \"No physical interaction demonstrated\"]\n    },\n    {\n      \"year\": 2026,\n      \"claim\": \"Refined the male-fertility role by localizing nphp4 to Sertoli cells and showing it maintains the spermatogonial niche, with loss causing Sertoli apoptosis and germ cell depletion.\",\n      \"evidence\": \"In situ hybridization, CRISPR/Cas9 knockout, EM and transcriptomics in medaka\",\n      \"pmids\": [\"41782365\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether the niche role is ciliary or signaling-based unresolved\", \"Mitochondrial damage mechanism undefined\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"How NPHP4's ciliary gating, actin-organizing, and Hippo-regulatory activities are mechanistically integrated within a single protein remains unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of NPHP4 barrier assembly\", \"Connection between cilium-based and Hippo-signaling roles unestablished\", \"Substrate/recruitment hierarchy at the transition zone undefined\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0008092\", \"supporting_discovery_ids\": [2]},\n      {\"term_id\": \"GO:0098772\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"GO:0060090\", \"supporting_discovery_ids\": [1, 2]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005929\", \"supporting_discovery_ids\": [1, 3]},\n      {\"term_id\": \"GO:0005815\", \"supporting_discovery_ids\": [2]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-162582\", \"supporting_discovery_ids\": [0]},\n      {\"term_id\": \"R-HSA-1852241\", \"supporting_discovery_ids\": [1, 2]}\n    ],\n    \"complexes\": [\"NPHP4-Inturned-DAAM1 complex\", \"ciliary transition zone\"],\n    \"partners\": [\"LATS1\", \"Inturned\", \"DAAM1\", \"RPGRIP1\", \"NPHP1\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":6,"faith_total":6,"faith_pct":100.0}}