{"gene":"CFAP74","run_date":"2026-06-09T22:57:18","timeline":{"discoveries":[{"year":2020,"finding":"Biallelic missense mutations in CFAP74 (compound heterozygous variants in two unrelated patients) result in absence of CFAP74 protein in sperm as confirmed by immunofluorescence, associated with the MMAF (multiple morphological abnormalities of sperm flagella) phenotype and potential PCD, establishing CFAP74 as required for normal sperm flagellar morphology.","method":"Whole-exome sequencing, immunofluorescence on patient sperm samples","journal":"Journal of human genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — single lab, immunofluorescence confirmed protein absence in patient sperm with biallelic variants, but no in vitro reconstitution or mechanistic pathway placement","pmids":["32555313"],"is_preprint":false},{"year":2024,"finding":"Pathogenic variants in CFAP74 cause primary ciliary dyskinesia with a defective C1d projection of the ciliary central apparatus; affected individuals exhibit insufficient ciliary clearance demonstrated by in vitro ciliary transport assays, despite normal ciliary ultrastructure by TEM and normal ciliary beating by high-speed videomicroscopy.","method":"High-throughput sequencing, in vitro ciliary transport assays, transmission electron microscopy, high-speed videomicroscopy","journal":"The European respiratory journal","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — functional ciliary transport assay directly demonstrates impaired clearance in CFAP74 variant individuals; multiple orthogonal methods in one study","pmids":["39362668"],"is_preprint":false},{"year":2022,"finding":"Morpholino-mediated knockdown of cfap74 in zebrafish caused abnormalities in cardiac looping, disrupted expression of early left-right signaling molecules, and impaired Kupffer's vesicle organogenesis and ciliogenesis, establishing CFAP74 as required for left-right patterning via ciliogenesis.","method":"Zebrafish morpholino knockdown, whole-mount in situ hybridization, immunostaining, high-speed cilia video microscopy","journal":"PLoS genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — loss-of-function in vivo model with defined cellular phenotype (Kupffer's vesicle/ciliogenesis defect) and pathway placement (laterality/left-right signaling); single lab but multiple orthogonal methods","pmids":["36459505"],"is_preprint":false},{"year":2025,"finding":"CFAP74 localizes along the entire flagellum of spermatozoa as shown by immunofluorescence; missense variants in CFAP74 (c.2452C>T and c.3044T>C compound heterozygous, or homozygous c.3532G>A) do not disrupt protein expression or subcellular localization but are associated with flagellar ultrastructural defects including thinner midpiece, disorganized mitochondrial sheath, and axonemal abnormalities.","method":"Immunofluorescence, scanning electron microscopy, transmission electron microscopy, whole-exome sequencing","journal":"Annals of human genetics","confidence":"Medium","confidence_rationale":"Tier 2 / Weak — direct localization experiment showing CFAP74 along entire flagellum; ultrastructural defects characterized in patients; single lab, no in vitro reconstitution","pmids":["41117181"],"is_preprint":false},{"year":2025,"finding":"CFAP119 physically interacts with CFAP74 as validated by co-immunoprecipitation, placing CFAP74 within a protein interaction network relevant to sperm flagellum development.","method":"Co-immunoprecipitation (in vitro validation of in silico predicted interaction)","journal":"The world journal of men's health","confidence":"Low","confidence_rationale":"Tier 3 / Weak — single co-IP experiment from a paper focused on CFAP119, not CFAP74; no reciprocal pull-down or additional orthogonal validation reported","pmids":["40759592"],"is_preprint":false},{"year":2024,"finding":"CEP112 forms RNA granules during spermiogenesis that enrich CFAP74 mRNA among target mRNAs, and CEP112 orchestrates translational regulation of Cfap74 mRNA; this places CFAP74 as a translational target of CEP112-mediated phase separation during spermatid development.","method":"Multi-omics analyses, TRICK reporter assay, co-immunoprecipitation with mass spectrometry, in vitro liquid-liquid phase separation assay","journal":"Nature communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — TRICK assay and multi-omics provide direct evidence for translational regulation of Cfap74 mRNA by CEP112; multiple orthogonal methods; finding is about CEP112 acting on Cfap74 mRNA rather than CFAP74 protein mechanism per se","pmids":["39349455"],"is_preprint":false}],"current_model":"CFAP74 is a cilia- and flagella-associated protein that localizes along the entire sperm flagellum and is required for normal axonemal structure (specifically the C1d projection of the ciliary central apparatus), sperm flagellar integrity, mucociliary clearance, and left-right patterning via Kupffer's vesicle ciliogenesis; biallelic loss-of-function variants cause MMAF, primary ciliary dyskinesia, and laterality defects, while its mRNA is post-transcriptionally regulated by CEP112-mediated phase separation during spermiogenesis and its protein physically interacts with CFAP119 in the flagellar assembly network."},"narrative":{"mechanistic_narrative":"CFAP74 is a cilia- and flagella-associated protein required for the structural integrity and motile function of motile cilia and sperm flagella across multiple tissues [PMID:32555313, PMID:39362668, PMID:36459505]. In spermatozoa it localizes along the entire length of the flagellum, and its loss or pathogenic variation is associated with multiple morphological abnormalities of sperm flagella, including a thinner midpiece, disorganized mitochondrial sheath, and axonemal defects [PMID:32555313, PMID:41117181]. In respiratory cilia, pathogenic CFAP74 variants cause primary ciliary dyskinesia characterized by a defective C1d projection of the ciliary central apparatus and insufficient mucociliary clearance, despite grossly normal ciliary ultrastructure and beating [PMID:39362668]. CFAP74 is also required for left-right body patterning: knockdown disrupts Kupffer's vesicle organogenesis and ciliogenesis and perturbs early left-right signaling and cardiac looping [PMID:36459505]. During spermiogenesis, Cfap74 mRNA is a translational target of CEP112-mediated RNA granule phase separation [PMID:39349455], and the CFAP74 protein physically associates with CFAP119 within the flagellar assembly interaction network [PMID:40759592]. Beyond these localization, interaction, and loss-of-function phenotype data, the precise biochemical role of CFAP74 within the central apparatus has not been mechanistically resolved in the available corpus.","teleology":[{"year":2020,"claim":"Established that CFAP74 is genetically required for normal sperm flagellar morphology by linking biallelic variants to loss of the protein and the MMAF phenotype.","evidence":"Whole-exome sequencing and immunofluorescence on patient sperm","pmids":["32555313"],"confidence":"Medium","gaps":["No mechanistic placement within axonemal structure","No in vitro reconstitution of CFAP74 function","Functional consequence for ciliary motility not assessed"]},{"year":2022,"claim":"Showed CFAP74 acts in left-right patterning by demonstrating that its loss disrupts Kupffer's vesicle ciliogenesis and downstream laterality signaling.","evidence":"Zebrafish morpholino knockdown with in situ hybridization, immunostaining, and high-speed cilia videomicroscopy","pmids":["36459505"],"confidence":"Medium","gaps":["Morpholino specificity not corroborated by genetic mutant","Molecular role of CFAP74 within cilia not defined","Link between sperm and node ciliary defects unresolved"]},{"year":2024,"claim":"Defined the structural correlate of CFAP74 dysfunction in respiratory cilia by tying pathogenic variants to a defective C1d central-apparatus projection and impaired clearance.","evidence":"High-throughput sequencing, in vitro ciliary transport assays, TEM, and high-speed videomicroscopy in PCD individuals","pmids":["39362668"],"confidence":"Medium","gaps":["How CFAP74 builds or stabilizes the C1d projection unknown","Discordance between normal beat/ultrastructure and impaired clearance unexplained","No biochemical characterization of CFAP74 within central apparatus"]},{"year":2024,"claim":"Placed Cfap74 mRNA within post-transcriptional control of spermiogenesis by identifying it as a translational target of CEP112-driven RNA granule phase separation.","evidence":"Multi-omics, TRICK reporter assay, co-IP/MS, and in vitro phase separation assay","pmids":["39349455"],"confidence":"Medium","gaps":["Effect of dysregulated Cfap74 translation on protein function not tested","Finding centers on CEP112 rather than CFAP74 protein mechanism","Timing of CFAP74 protein deposition in flagellum not mapped"]},{"year":2025,"claim":"Demonstrated CFAP74 localizes along the entire flagellum and that some missense variants impair flagellar ultrastructure without abolishing protein expression or localization.","evidence":"Immunofluorescence, scanning and transmission electron microscopy, whole-exome sequencing in patients","pmids":["41117181"],"confidence":"Medium","gaps":["Mechanism by which localization-competent variants cause defects unknown","No structure-function mapping of variant residues","Single lab without reconstitution"]},{"year":2025,"claim":"Began defining the CFAP74 interaction network by validating a direct physical interaction with CFAP119 relevant to flagellum development.","evidence":"Co-immunoprecipitation validating an in silico predicted interaction","pmids":["40759592"],"confidence":"Low","gaps":["Single co-IP without reciprocal pull-down or orthogonal validation","Study focused on CFAP119, not CFAP74","Functional consequence of the interaction untested"]},{"year":null,"claim":"The direct biochemical activity of CFAP74 within the central apparatus and how it stabilizes the C1d projection remain unresolved.","evidence":"","pmids":[],"confidence":"Medium","gaps":["No structural model of CFAP74 in the axoneme","No comprehensive interactome beyond CFAP119","No reconstitution linking molecular activity to the C1d defect"]}],"mechanism_profile":{"molecular_activity":[],"localization":[{"term_id":"GO:0005929","term_label":"cilium","supporting_discovery_ids":[1,2,3]},{"term_id":"GO:0005856","term_label":"cytoskeleton","supporting_discovery_ids":[3]}],"pathway":[{"term_id":"R-HSA-1852241","term_label":"Organelle biogenesis and maintenance","supporting_discovery_ids":[1,2]},{"term_id":"R-HSA-1474165","term_label":"Reproduction","supporting_discovery_ids":[0,3]}],"complexes":[],"partners":["CFAP119"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q9C0B2","full_name":"Cilia- and flagella-associated protein 74","aliases":[],"length_aa":1584,"mass_kda":178.6,"function":"As part of the central apparatus of the cilium axoneme may play a role in cilium movement. May play an important role in sperm architecture and function","subcellular_location":"Cytoplasm, cytoskeleton, cilium axoneme; Cytoplasm, cytoskeleton, flagellum axoneme","url":"https://www.uniprot.org/uniprotkb/Q9C0B2/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/CFAP74","classification":"Not Classified","n_dependent_lines":0,"n_total_lines":74,"dependency_fraction":0.0},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/CFAP74","total_profiled":1310},"omim":[{"mim_id":"620197","title":"CILIARY DYSKINESIA, PRIMARY, 49, WITHOUT SITUS INVERSUS; CILD49","url":"https://www.omim.org/entry/620197"},{"mim_id":"620187","title":"CILIA- AND FLAGELLA-ASSOCIATED PROTEIN 74; CFAP74","url":"https://www.omim.org/entry/620187"},{"mim_id":"618704","title":"CILIA- AND FLAGELLA-ASSOCIATED PROTEIN 221; CFAP221","url":"https://www.omim.org/entry/618704"},{"mim_id":"618543","title":"CILIA- AND FLAGELLA-ASSOCIATED PROTEIN 46; CFAP46","url":"https://www.omim.org/entry/618543"},{"mim_id":"279000","title":"CILIARY DYSKINESIA, PRIMARY, 55; CILD55","url":"https://www.omim.org/entry/279000"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"","locations":[],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"choroid plexus","ntpm":3.6},{"tissue":"fallopian tube","ntpm":6.5},{"tissue":"testis","ntpm":4.8}],"url":"https://www.proteinatlas.org/search/CFAP74"},"hgnc":{"alias_symbol":["FLJ45476"],"prev_symbol":["C1orf222","KIAA1751"]},"alphafold":{"accession":"Q9C0B2","domains":[{"cath_id":"2.60.40.10","chopping":"512-612","consensus_level":"medium","plddt":81.6176,"start":512,"end":612},{"cath_id":"2.60.40.10","chopping":"803-915","consensus_level":"high","plddt":85.5757,"start":803,"end":915},{"cath_id":"2.60.40.10","chopping":"917-1017","consensus_level":"medium","plddt":86.6134,"start":917,"end":1017},{"cath_id":"2.60.40.10","chopping":"1019-1049_1069-1124_1178-1211_1219-1238","consensus_level":"medium","plddt":82.4376,"start":1019,"end":1238},{"cath_id":"2.60.40.10","chopping":"1239-1340","consensus_level":"medium","plddt":83.1477,"start":1239,"end":1340},{"cath_id":"-","chopping":"1482-1487_1532-1541_1572-1584","consensus_level":"medium","plddt":64.2786,"start":1482,"end":1584},{"cath_id":"1.10.287","chopping":"71-295","consensus_level":"medium","plddt":80.6988,"start":71,"end":295}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9C0B2","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9C0B2-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9C0B2-F1-predicted_aligned_error_v6.png","plddt_mean":69.31},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=CFAP74","jax_strain_url":"https://www.jax.org/strain/search?query=CFAP74"},"sequence":{"accession":"Q9C0B2","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9C0B2.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9C0B2/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9C0B2"}},"corpus_meta":[{"pmid":"32555313","id":"PMC_32555313","title":"Biallelic mutations of CFAP74 may cause human primary ciliary dyskinesia and MMAF phenotype.","date":"2020","source":"Journal of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/32555313","citation_count":45,"is_preprint":false},{"pmid":"23337955","id":"PMC_23337955","title":"Analysis of differentially expressed genes and microRNAs in alcoholic liver disease.","date":"2013","source":"International journal of molecular medicine","url":"https://pubmed.ncbi.nlm.nih.gov/23337955","citation_count":37,"is_preprint":false},{"pmid":"39349455","id":"PMC_39349455","title":"CEP112 coordinates translational regulation of essential fertility genes during spermiogenesis through phase separation in humans and mice.","date":"2024","source":"Nature communications","url":"https://pubmed.ncbi.nlm.nih.gov/39349455","citation_count":19,"is_preprint":false},{"pmid":"36980985","id":"PMC_36980985","title":"Genome-Wide Scan of Wool Production Traits in Akkaraman Sheep.","date":"2023","source":"Genes","url":"https://pubmed.ncbi.nlm.nih.gov/36980985","citation_count":17,"is_preprint":false},{"pmid":"39362668","id":"PMC_39362668","title":"Pathogenic variants in CFAP46, CFAP54, CFAP74 and CFAP221 cause primary ciliary dyskinesia with a defective C1d projection of the central apparatus.","date":"2024","source":"The European respiratory journal","url":"https://pubmed.ncbi.nlm.nih.gov/39362668","citation_count":15,"is_preprint":false},{"pmid":"36459505","id":"PMC_36459505","title":"LOF variants identifying candidate genes of laterality defects patients with congenital heart disease.","date":"2022","source":"PLoS genetics","url":"https://pubmed.ncbi.nlm.nih.gov/36459505","citation_count":9,"is_preprint":false},{"pmid":"34743693","id":"PMC_34743693","title":"Comparative methylation and RNA-seq expression analysis in CpG context to identify genes involved in Backfat vs. Liver diversification in Nanchukmacdon Pig.","date":"2021","source":"BMC genomics","url":"https://pubmed.ncbi.nlm.nih.gov/34743693","citation_count":8,"is_preprint":false},{"pmid":"35117778","id":"PMC_35117778","title":"Comparison of whole exome sequencing in circulating tumor cells of primitive and metastatic nasopharyngeal carcinoma.","date":"2020","source":"Translational cancer research","url":"https://pubmed.ncbi.nlm.nih.gov/35117778","citation_count":7,"is_preprint":false},{"pmid":"33177874","id":"PMC_33177874","title":"HNRNPCL1, PRAMEF1, CFAP74, and DFFB: Common Potential Biomarkers for Sporadic and Suspected Lynch Syndrome Endometrial Cancer.","date":"2020","source":"Cancer management and research","url":"https://pubmed.ncbi.nlm.nih.gov/33177874","citation_count":5,"is_preprint":false},{"pmid":"37750990","id":"PMC_37750990","title":"Genomic selection pressure discovery using site-frequency spectrum and reduced local variability statistics in Pakistani Dera-Din-Panah goat.","date":"2023","source":"Tropical animal health and production","url":"https://pubmed.ncbi.nlm.nih.gov/37750990","citation_count":3,"is_preprint":false},{"pmid":"40759592","id":"PMC_40759592","title":"Identification of a Novel Biallelic CFAP119 Variant in an Infertile Man with Asthenoteratozoospermia.","date":"2025","source":"The world journal of men's health","url":"https://pubmed.ncbi.nlm.nih.gov/40759592","citation_count":1,"is_preprint":false},{"pmid":"41117181","id":"PMC_41117181","title":"CFAP74 Variants Could Cause Male Infertility With the Asthenoteratozoospermia Phenotype.","date":"2025","source":"Annals of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/41117181","citation_count":0,"is_preprint":false},{"pmid":"40272718","id":"PMC_40272718","title":"Establishing the causative link between CFAP221 variants and asthenoteratozoospermia in humans.","date":"2025","source":"Journal of assisted reproduction and genetics","url":"https://pubmed.ncbi.nlm.nih.gov/40272718","citation_count":0,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":9401,"output_tokens":1594,"usd":0.026056,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":8385,"output_tokens":2236,"usd":0.048912,"stage2_stop_reason":"end_turn"},"total_usd":0.074968,"stage1_batch_id":"msgbatch_01ACAxJQabDsht39JXeWG22d","stage2_batch_id":"msgbatch_01QEU22A9U5sbPTgsMzTmvSf","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2020,\n      \"finding\": \"Biallelic missense mutations in CFAP74 (compound heterozygous variants in two unrelated patients) result in absence of CFAP74 protein in sperm as confirmed by immunofluorescence, associated with the MMAF (multiple morphological abnormalities of sperm flagella) phenotype and potential PCD, establishing CFAP74 as required for normal sperm flagellar morphology.\",\n      \"method\": \"Whole-exome sequencing, immunofluorescence on patient sperm samples\",\n      \"journal\": \"Journal of human genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — single lab, immunofluorescence confirmed protein absence in patient sperm with biallelic variants, but no in vitro reconstitution or mechanistic pathway placement\",\n      \"pmids\": [\"32555313\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"Pathogenic variants in CFAP74 cause primary ciliary dyskinesia with a defective C1d projection of the ciliary central apparatus; affected individuals exhibit insufficient ciliary clearance demonstrated by in vitro ciliary transport assays, despite normal ciliary ultrastructure by TEM and normal ciliary beating by high-speed videomicroscopy.\",\n      \"method\": \"High-throughput sequencing, in vitro ciliary transport assays, transmission electron microscopy, high-speed videomicroscopy\",\n      \"journal\": \"The European respiratory journal\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — functional ciliary transport assay directly demonstrates impaired clearance in CFAP74 variant individuals; multiple orthogonal methods in one study\",\n      \"pmids\": [\"39362668\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"Morpholino-mediated knockdown of cfap74 in zebrafish caused abnormalities in cardiac looping, disrupted expression of early left-right signaling molecules, and impaired Kupffer's vesicle organogenesis and ciliogenesis, establishing CFAP74 as required for left-right patterning via ciliogenesis.\",\n      \"method\": \"Zebrafish morpholino knockdown, whole-mount in situ hybridization, immunostaining, high-speed cilia video microscopy\",\n      \"journal\": \"PLoS genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — loss-of-function in vivo model with defined cellular phenotype (Kupffer's vesicle/ciliogenesis defect) and pathway placement (laterality/left-right signaling); single lab but multiple orthogonal methods\",\n      \"pmids\": [\"36459505\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"CFAP74 localizes along the entire flagellum of spermatozoa as shown by immunofluorescence; missense variants in CFAP74 (c.2452C>T and c.3044T>C compound heterozygous, or homozygous c.3532G>A) do not disrupt protein expression or subcellular localization but are associated with flagellar ultrastructural defects including thinner midpiece, disorganized mitochondrial sheath, and axonemal abnormalities.\",\n      \"method\": \"Immunofluorescence, scanning electron microscopy, transmission electron microscopy, whole-exome sequencing\",\n      \"journal\": \"Annals of human genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Weak — direct localization experiment showing CFAP74 along entire flagellum; ultrastructural defects characterized in patients; single lab, no in vitro reconstitution\",\n      \"pmids\": [\"41117181\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"CFAP119 physically interacts with CFAP74 as validated by co-immunoprecipitation, placing CFAP74 within a protein interaction network relevant to sperm flagellum development.\",\n      \"method\": \"Co-immunoprecipitation (in vitro validation of in silico predicted interaction)\",\n      \"journal\": \"The world journal of men's health\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — single co-IP experiment from a paper focused on CFAP119, not CFAP74; no reciprocal pull-down or additional orthogonal validation reported\",\n      \"pmids\": [\"40759592\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"CEP112 forms RNA granules during spermiogenesis that enrich CFAP74 mRNA among target mRNAs, and CEP112 orchestrates translational regulation of Cfap74 mRNA; this places CFAP74 as a translational target of CEP112-mediated phase separation during spermatid development.\",\n      \"method\": \"Multi-omics analyses, TRICK reporter assay, co-immunoprecipitation with mass spectrometry, in vitro liquid-liquid phase separation assay\",\n      \"journal\": \"Nature communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — TRICK assay and multi-omics provide direct evidence for translational regulation of Cfap74 mRNA by CEP112; multiple orthogonal methods; finding is about CEP112 acting on Cfap74 mRNA rather than CFAP74 protein mechanism per se\",\n      \"pmids\": [\"39349455\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"CFAP74 is a cilia- and flagella-associated protein that localizes along the entire sperm flagellum and is required for normal axonemal structure (specifically the C1d projection of the ciliary central apparatus), sperm flagellar integrity, mucociliary clearance, and left-right patterning via Kupffer's vesicle ciliogenesis; biallelic loss-of-function variants cause MMAF, primary ciliary dyskinesia, and laterality defects, while its mRNA is post-transcriptionally regulated by CEP112-mediated phase separation during spermiogenesis and its protein physically interacts with CFAP119 in the flagellar assembly network.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"CFAP74 is a cilia- and flagella-associated protein required for the structural integrity and motile function of motile cilia and sperm flagella across multiple tissues [#0, #1, #2]. In spermatozoa it localizes along the entire length of the flagellum, and its loss or pathogenic variation is associated with multiple morphological abnormalities of sperm flagella, including a thinner midpiece, disorganized mitochondrial sheath, and axonemal defects [#0, #3]. In respiratory cilia, pathogenic CFAP74 variants cause primary ciliary dyskinesia characterized by a defective C1d projection of the ciliary central apparatus and insufficient mucociliary clearance, despite grossly normal ciliary ultrastructure and beating [#1]. CFAP74 is also required for left-right body patterning: knockdown disrupts Kupffer's vesicle organogenesis and ciliogenesis and perturbs early left-right signaling and cardiac looping [#2]. During spermiogenesis, Cfap74 mRNA is a translational target of CEP112-mediated RNA granule phase separation [#5], and the CFAP74 protein physically associates with CFAP119 within the flagellar assembly interaction network [#4]. Beyond these localization, interaction, and loss-of-function phenotype data, the precise biochemical role of CFAP74 within the central apparatus has not been mechanistically resolved in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 2020,\n      \"claim\": \"Established that CFAP74 is genetically required for normal sperm flagellar morphology by linking biallelic variants to loss of the protein and the MMAF phenotype.\",\n      \"evidence\": \"Whole-exome sequencing and immunofluorescence on patient sperm\",\n      \"pmids\": [\"32555313\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No mechanistic placement within axonemal structure\", \"No in vitro reconstitution of CFAP74 function\", \"Functional consequence for ciliary motility not assessed\"]\n    },\n    {\n      \"year\": 2022,\n      \"claim\": \"Showed CFAP74 acts in left-right patterning by demonstrating that its loss disrupts Kupffer's vesicle ciliogenesis and downstream laterality signaling.\",\n      \"evidence\": \"Zebrafish morpholino knockdown with in situ hybridization, immunostaining, and high-speed cilia videomicroscopy\",\n      \"pmids\": [\"36459505\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Morpholino specificity not corroborated by genetic mutant\", \"Molecular role of CFAP74 within cilia not defined\", \"Link between sperm and node ciliary defects unresolved\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Defined the structural correlate of CFAP74 dysfunction in respiratory cilia by tying pathogenic variants to a defective C1d central-apparatus projection and impaired clearance.\",\n      \"evidence\": \"High-throughput sequencing, in vitro ciliary transport assays, TEM, and high-speed videomicroscopy in PCD individuals\",\n      \"pmids\": [\"39362668\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"How CFAP74 builds or stabilizes the C1d projection unknown\", \"Discordance between normal beat/ultrastructure and impaired clearance unexplained\", \"No biochemical characterization of CFAP74 within central apparatus\"]\n    },\n    {\n      \"year\": 2024,\n      \"claim\": \"Placed Cfap74 mRNA within post-transcriptional control of spermiogenesis by identifying it as a translational target of CEP112-driven RNA granule phase separation.\",\n      \"evidence\": \"Multi-omics, TRICK reporter assay, co-IP/MS, and in vitro phase separation assay\",\n      \"pmids\": [\"39349455\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Effect of dysregulated Cfap74 translation on protein function not tested\", \"Finding centers on CEP112 rather than CFAP74 protein mechanism\", \"Timing of CFAP74 protein deposition in flagellum not mapped\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Demonstrated CFAP74 localizes along the entire flagellum and that some missense variants impair flagellar ultrastructure without abolishing protein expression or localization.\",\n      \"evidence\": \"Immunofluorescence, scanning and transmission electron microscopy, whole-exome sequencing in patients\",\n      \"pmids\": [\"41117181\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Mechanism by which localization-competent variants cause defects unknown\", \"No structure-function mapping of variant residues\", \"Single lab without reconstitution\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Began defining the CFAP74 interaction network by validating a direct physical interaction with CFAP119 relevant to flagellum development.\",\n      \"evidence\": \"Co-immunoprecipitation validating an in silico predicted interaction\",\n      \"pmids\": [\"40759592\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\"Single co-IP without reciprocal pull-down or orthogonal validation\", \"Study focused on CFAP119, not CFAP74\", \"Functional consequence of the interaction untested\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The direct biochemical activity of CFAP74 within the central apparatus and how it stabilizes the C1d projection remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"No structural model of CFAP74 in the axoneme\", \"No comprehensive interactome beyond CFAP119\", \"No reconstitution linking molecular activity to the C1d defect\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [],\n    \"localization\": [\n      {\"term_id\": \"GO:0005929\", \"supporting_discovery_ids\": [1, 2, 3]},\n      {\"term_id\": \"GO:0005856\", \"supporting_discovery_ids\": [3]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1852241\", \"supporting_discovery_ids\": [1, 2]},\n      {\"term_id\": \"R-HSA-1474165\", \"supporting_discovery_ids\": [0, 3]}\n    ],\n    \"complexes\": [],\n    \"partners\": [\"CFAP119\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"pairwise":"win","faith_supported":5,"faith_total":5,"faith_pct":100.0}}