{"gene":"CEP295NL","run_date":"2026-06-09T22:57:18","timeline":{"discoveries":[{"year":2009,"finding":"CEP295NL (DDC8) protein physically interacts with Trs4 (temperature-related sequence 4) in mouse testes, as confirmed by yeast two-hybrid screening, in vivo co-immunoprecipitation, and in vitro binding assays. CEP295NL co-localizes with Trs4 and Rshl-2 to the tails of mature spermatozoa.","method":"Yeast two-hybrid screening, in vivo and in vitro binding assays, co-localization","journal":"Biochemical and biophysical research communications","confidence":"Medium","confidence_rationale":"Tier 2 / Moderate — reciprocal binding confirmed by both in vivo and in vitro assays plus co-localization, single lab","pmids":["19706271"],"is_preprint":false},{"year":2023,"finding":"CEP295NL (DDC8) interacts with IQUB, RSPH3, GSTM1, and ODF1 in the yeast two-hybrid system, placing CEP295NL within the sperm radial spoke assembly network. CEP295NL was identified as a binding partner of IQUB, a protein that facilitates normal radial spoke assembly in sperm flagella.","method":"Yeast two-hybrid system, co-immunoprecipitation","journal":"Human reproduction (Oxford, England)","confidence":"Low","confidence_rationale":"Tier 3 / Weak — CEP295NL interaction reported as context for IQUB study; single method (yeast two-hybrid) cited for CEP295NL specifically, no direct functional validation of CEP295NL's role","pmids":["36355624"],"is_preprint":false},{"year":1997,"finding":"CEP295NL (DDC8) encodes a predicted hydrophilic protein of 533 amino acids (~62 kDa) with similarities to structural, cytoskeletal and associated proteins, and its mRNA is expressed during postmeiotic stages of spermatogenesis in mouse testes.","method":"Differential display, cDNA library screening, RNase protection assay, sequence analysis","journal":"Molecular human reproduction","confidence":"Low","confidence_rationale":"Tier 3 / Weak — initial characterization by expression assay and sequence homology; no functional mechanistic experiment performed","pmids":["9237247"],"is_preprint":false}],"current_model":"CEP295NL (DDC8) is a postmeiotically expressed spermatogenic protein that localizes to the tails of mature spermatozoa and physically associates with multiple sperm-tail proteins including Trs4/IQUB, RSPH3, GSTM1, and ODF1, suggesting a role in sperm flagellar/radial spoke assembly, though its precise molecular function remains undefined."},"narrative":{"mechanistic_narrative":"CEP295NL (DDC8) is a postmeiotically expressed spermatogenic protein that localizes to the tails of mature spermatozoa, where it physically associates with sperm-tail components [PMID:19706271]. It was first defined as a hydrophilic ~62 kDa protein bearing similarity to structural and cytoskeletal proteins, with mRNA restricted to postmeiotic stages of spermatogenesis in mouse testis [PMID:9237247]. CEP295NL binds Trs4 and co-localizes with Trs4 and Rshl-2 along the tails of mature spermatozoa, an interaction confirmed by yeast two-hybrid, co-immunoprecipitation, and in vitro binding [PMID:19706271]. Beyond these binding and expression observations, no catalytic activity or defined molecular mechanism for CEP295NL has been characterized in the available corpus.","teleology":[{"year":1997,"claim":"Established CEP295NL/DDC8 as a candidate spermatogenic gene by showing its mRNA is expressed specifically during postmeiotic spermatogenesis and encodes a protein resembling structural/cytoskeletal proteins.","evidence":"Differential display, cDNA library screening, RNase protection assay and sequence analysis in mouse testis","pmids":["9237247"],"confidence":"Low","gaps":["No functional mechanistic experiment performed; role inferred only from sequence homology","Protein product localization not determined at this stage","No interaction partners identified"]},{"year":2009,"claim":"Showed CEP295NL is a sperm-tail protein by demonstrating a direct physical interaction with Trs4 and co-localization with Trs4 and Rshl-2 in the tails of mature spermatozoa, linking it to flagellar structure.","evidence":"Yeast two-hybrid screening, in vivo co-IP, in vitro binding, and co-localization in mouse testis/spermatozoa","pmids":["19706271"],"confidence":"Medium","gaps":["Molecular function within the sperm tail not defined","No loss-of-function or knockout phenotype to establish a functional requirement","Single-lab finding"]},{"year":2023,"claim":"Placed CEP295NL within a sperm radial spoke assembly interaction network by identifying it as a binding partner of IQUB and of RSPH3, GSTM1, and ODF1.","evidence":"Yeast two-hybrid system and co-immunoprecipitation, reported as context within an IQUB-focused study","pmids":["36355624"],"confidence":"Low","gaps":["CEP295NL interactions supported mainly by yeast two-hybrid without dedicated functional validation of CEP295NL's role","Whether CEP295NL is required for radial spoke assembly untested","No reciprocal or in vivo confirmation specific to CEP295NL"]},{"year":null,"claim":"The precise molecular function of CEP295NL and its requirement in sperm flagellar/radial spoke assembly remain undefined.","evidence":"No loss-of-function, structural, or biochemical mechanistic study in the available corpus","pmids":[],"confidence":"Low","gaps":["No knockout or knockdown phenotype","No defined biochemical/catalytic activity","No structural basis for its protein interactions"]}],"mechanism_profile":{"molecular_activity":[],"localization":[{"term_id":"GO:0005929","term_label":"cilium","supporting_discovery_ids":[0]}],"pathway":[],"complexes":[],"partners":["IQUB","RSPH3","GSTM1","ODF1"],"other_free_text":[]}},"prefetch_data":{"uniprot":{"accession":"Q96MC4","full_name":"CEP295 N-terminal-like protein","aliases":["KIAA1731 N-terminal like protein"],"length_aa":621,"mass_kda":69.8,"function":"","subcellular_location":"Cell projection, cilium","url":"https://www.uniprot.org/uniprotkb/Q96MC4/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/CEP295NL","classification":"Not Classified","n_dependent_lines":2,"n_total_lines":1208,"dependency_fraction":0.0016556291390728477},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/CEP295NL","total_profiled":1310},"omim":[{"mim_id":"620557","title":"IQ MOTIF- AND UBIQUITIN DOMAIN-CONTAINING PROTEIN; IQUB","url":"https://www.omim.org/entry/620557"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Vesicles","reliability":"Approved"}],"tissue_specificity":"Tissue enriched","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"testis","ntpm":26.1}],"url":"https://www.proteinatlas.org/search/CEP295NL"},"hgnc":{"alias_symbol":["DDC8"],"prev_symbol":["KIAA1731NL"]},"alphafold":{"accession":"Q96MC4","domains":[],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96MC4","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q96MC4-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q96MC4-F1-predicted_aligned_error_v6.png","plddt_mean":57.81},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=CEP295NL","jax_strain_url":"https://www.jax.org/strain/search?query=CEP295NL"},"sequence":{"accession":"Q96MC4","fasta_url":"https://rest.uniprot.org/uniprotkb/Q96MC4.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q96MC4/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q96MC4"}},"corpus_meta":[{"pmid":"16985004","id":"PMC_16985004","title":"Potential regulatory relationship between the nested gene DDC8 and its host gene tissue inhibitor of metalloproteinase-2.","date":"2006","source":"Physiological genomics","url":"https://pubmed.ncbi.nlm.nih.gov/16985004","citation_count":19,"is_preprint":false},{"pmid":"9237247","id":"PMC_9237247","title":"Differential display to identify and isolate novel genes expressed during spermatogenesis.","date":"1997","source":"Molecular human reproduction","url":"https://pubmed.ncbi.nlm.nih.gov/9237247","citation_count":14,"is_preprint":false},{"pmid":"36355624","id":"PMC_36355624","title":"IQUB deficiency causes male infertility by affecting the activity of p-ERK1/2/RSPH3.","date":"2023","source":"Human reproduction (Oxford, England)","url":"https://pubmed.ncbi.nlm.nih.gov/36355624","citation_count":8,"is_preprint":false},{"pmid":"19706271","id":"PMC_19706271","title":"Male germ cell-specific protein Trs4 binds to multiple proteins.","date":"2009","source":"Biochemical and biophysical research communications","url":"https://pubmed.ncbi.nlm.nih.gov/19706271","citation_count":7,"is_preprint":false}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":4511,"output_tokens":790,"usd":0.012691,"stage1_stop_reason":"end_turn"},"stage2":{"model":"claude-opus-4-8","input_tokens":7190,"output_tokens":1398,"usd":0.03545,"stage2_stop_reason":"end_turn"},"total_usd":0.048141,"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\": 2009,\n      \"finding\": \"CEP295NL (DDC8) protein physically interacts with Trs4 (temperature-related sequence 4) in mouse testes, as confirmed by yeast two-hybrid screening, in vivo co-immunoprecipitation, and in vitro binding assays. CEP295NL co-localizes with Trs4 and Rshl-2 to the tails of mature spermatozoa.\",\n      \"method\": \"Yeast two-hybrid screening, in vivo and in vitro binding assays, co-localization\",\n      \"journal\": \"Biochemical and biophysical research communications\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 / Moderate — reciprocal binding confirmed by both in vivo and in vitro assays plus co-localization, single lab\",\n      \"pmids\": [\"19706271\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"CEP295NL (DDC8) interacts with IQUB, RSPH3, GSTM1, and ODF1 in the yeast two-hybrid system, placing CEP295NL within the sperm radial spoke assembly network. CEP295NL was identified as a binding partner of IQUB, a protein that facilitates normal radial spoke assembly in sperm flagella.\",\n      \"method\": \"Yeast two-hybrid system, co-immunoprecipitation\",\n      \"journal\": \"Human reproduction (Oxford, England)\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — CEP295NL interaction reported as context for IQUB study; single method (yeast two-hybrid) cited for CEP295NL specifically, no direct functional validation of CEP295NL's role\",\n      \"pmids\": [\"36355624\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 1997,\n      \"finding\": \"CEP295NL (DDC8) encodes a predicted hydrophilic protein of 533 amino acids (~62 kDa) with similarities to structural, cytoskeletal and associated proteins, and its mRNA is expressed during postmeiotic stages of spermatogenesis in mouse testes.\",\n      \"method\": \"Differential display, cDNA library screening, RNase protection assay, sequence analysis\",\n      \"journal\": \"Molecular human reproduction\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 / Weak — initial characterization by expression assay and sequence homology; no functional mechanistic experiment performed\",\n      \"pmids\": [\"9237247\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"CEP295NL (DDC8) is a postmeiotically expressed spermatogenic protein that localizes to the tails of mature spermatozoa and physically associates with multiple sperm-tail proteins including Trs4/IQUB, RSPH3, GSTM1, and ODF1, suggesting a role in sperm flagellar/radial spoke assembly, though its precise molecular function remains undefined.\"\n}\n```","stage2_raw":"{\n  \"mechanistic_narrative\": \"CEP295NL (DDC8) is a postmeiotically expressed spermatogenic protein that localizes to the tails of mature spermatozoa, where it physically associates with sperm-tail components [#0]. It was first defined as a hydrophilic ~62 kDa protein bearing similarity to structural and cytoskeletal proteins, with mRNA restricted to postmeiotic stages of spermatogenesis in mouse testis [#2]. CEP295NL binds Trs4 and co-localizes with Trs4 and Rshl-2 along the tails of mature spermatozoa, an interaction confirmed by yeast two-hybrid, co-immunoprecipitation, and in vitro binding [#0]. Beyond these binding and expression observations, no catalytic activity or defined molecular mechanism for CEP295NL has been characterized in the available corpus.\",\n  \"teleology\": [\n    {\n      \"year\": 1997,\n      \"claim\": \"Established CEP295NL/DDC8 as a candidate spermatogenic gene by showing its mRNA is expressed specifically during postmeiotic spermatogenesis and encodes a protein resembling structural/cytoskeletal proteins.\",\n      \"evidence\": \"Differential display, cDNA library screening, RNase protection assay and sequence analysis in mouse testis\",\n      \"pmids\": [\"9237247\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No functional mechanistic experiment performed; role inferred only from sequence homology\",\n        \"Protein product localization not determined at this stage\",\n        \"No interaction partners identified\"\n      ]\n    },\n    {\n      \"year\": 2009,\n      \"claim\": \"Showed CEP295NL is a sperm-tail protein by demonstrating a direct physical interaction with Trs4 and co-localization with Trs4 and Rshl-2 in the tails of mature spermatozoa, linking it to flagellar structure.\",\n      \"evidence\": \"Yeast two-hybrid screening, in vivo co-IP, in vitro binding, and co-localization in mouse testis/spermatozoa\",\n      \"pmids\": [\"19706271\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\n        \"Molecular function within the sperm tail not defined\",\n        \"No loss-of-function or knockout phenotype to establish a functional requirement\",\n        \"Single-lab finding\"\n      ]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Placed CEP295NL within a sperm radial spoke assembly interaction network by identifying it as a binding partner of IQUB and of RSPH3, GSTM1, and ODF1.\",\n      \"evidence\": \"Yeast two-hybrid system and co-immunoprecipitation, reported as context within an IQUB-focused study\",\n      \"pmids\": [\"36355624\"],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"CEP295NL interactions supported mainly by yeast two-hybrid without dedicated functional validation of CEP295NL's role\",\n        \"Whether CEP295NL is required for radial spoke assembly untested\",\n        \"No reciprocal or in vivo confirmation specific to CEP295NL\"\n      ]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The precise molecular function of CEP295NL and its requirement in sperm flagellar/radial spoke assembly remain undefined.\",\n      \"evidence\": \"No loss-of-function, structural, or biochemical mechanistic study in the available corpus\",\n      \"pmids\": [],\n      \"confidence\": \"Low\",\n      \"gaps\": [\n        \"No knockout or knockdown phenotype\",\n        \"No defined biochemical/catalytic activity\",\n        \"No structural basis for its protein interactions\"\n      ]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [],\n    \"localization\": [\n      {\"term_id\": \"GO:0005929\", \"supporting_discovery_ids\": [0]}\n    ],\n    \"pathway\": [],\n    \"complexes\": [],\n    \"partners\": [\"IQUB\", \"RSPH3\", \"GSTM1\", \"ODF1\"],\n    \"other_free_text\": []\n  }\n}","audit_flag":null,"evaluation":{"faith_supported":3,"faith_total":3,"faith_pct":100.0}}