{"gene":"RSPH9","run_date":"2026-04-28T20:42:06","timeline":{"discoveries":[{"year":2009,"finding":"RSPH9 encodes a protein component of the axonemal radial spoke head; mutations cause primary ciliary dyskinesia with central-microtubular-pair abnormalities; knockdown of RSPH9 orthologs in zebrafish and Chlamydomonas disrupts normal motile cilia movement, and reintroduction of gene expression restores normal beat pattern in zebrafish.","method":"Genetic linkage analysis, positional cloning, in situ hybridization (murine Rsph9), zebrafish knockdown/rescue, Chlamydomonas knockdown","journal":"American journal of human genetics","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods (genetics, in situ hybridization, zebrafish knockdown+rescue, Chlamydomonas), replicated in two model organisms, highly cited foundational paper","pmids":["19200523"],"is_preprint":false},{"year":2015,"finding":"RSPH4A is the core protein of the radial spoke head; absence of RSPH4A (due to RSPH4A mutations) results in deficient axonemal assembly of both RSPH1 and RSPH9; RSPH1 mutations cause loss of RSPH9 from the axoneme; RSPH9 mutations result in absence of RSPH9 but do not affect axonemal assembly of RSPH1 or RSPH4A, placing RSPH9 downstream of both RSPH4A and RSPH1 in radial spoke head assembly.","method":"High-resolution immunofluorescence analysis of human respiratory cilia from patients with defined biallelic mutations in RSPH9, RSPH4A, and RSPH1","journal":"American journal of respiratory cell and molecular biology","confidence":"High","confidence_rationale":"Tier 2 — reciprocal immunofluorescence across multiple patient genotypes defining assembly hierarchy, replicated across 16 families, highly cited","pmids":["25789548"],"is_preprint":false},{"year":2014,"finding":"RSPH1, RSPH4A, and RSPH9 are all components of the 'head' structure of ciliary radial spoke complexes; high-resolution immunofluorescence showed loss of RSPH4A and RSPH9 along with RSPH1 from RSPH1-mutated cilia, suggesting RSPH1 mutations may result in loss of the entire spoke head structure; proposed mechanism: CP loss arises from instability due to loss of normal radial spoke head tethering.","method":"Targeted NGS gene panel sequencing, ultrastructural analysis by TEM, high-resolution immunofluorescence of patient cilia","journal":"Human molecular genetics","confidence":"High","confidence_rationale":"Tier 2 — multiple orthogonal methods (genetics, TEM, immunofluorescence), defines epistatic relationship in spoke head assembly","pmids":["24518672"],"is_preprint":false},{"year":2018,"finding":"Mouse Rsph9 is essential for both radial spoke head assembly and central pair microtubule maintenance in ependymal motile cilia; RNAi depletion of Rsph9 in mouse ependymal cilia caused near-complete central pair loss, altered beat pattern from planar to rotational, and marked downregulation of multiple radial spoke proteins including those in the head.","method":"RNAi knockdown in mouse ependymal cilia, high-speed video microscopy, immunofluorescence, TEM","journal":"Biology of the cell","confidence":"High","confidence_rationale":"Tier 2 — clean RNAi KD with multiple orthogonal readouts (beat pattern, ultrastructure, protein localization) in mammalian cells","pmids":["30383886"],"is_preprint":false},{"year":2018,"finding":"RSPH9 is required for RSPH6A-dependent flagellar assembly; in Rsph6a knockout mice, RSPH9 disappears from sperm flagella, indicating RSPH9 stability/localization depends on RSPH6A.","method":"Rsph6a knockout mouse model, immunofluorescence of sperm flagella","journal":"Journal of cell science","confidence":"Medium","confidence_rationale":"Tier 2 — clean KO with defined molecular phenotype (loss of RSPH9 localization), single lab","pmids":["30185526"],"is_preprint":false},{"year":2020,"finding":"Deletion of Rsph9 in mice leads to neonatal hydrocephalus; Rsph9-/- ependymal cilia show lower beating amplitude and irregular rotational beating pattern, increased centriolar patch size, and frequent abnormal ectopic ciliary membrane inclusions, while overall axonemal organization is largely preserved.","method":"Rsph9 knockout mouse model, high-speed video microscopy, TEM, immunofluorescence","journal":"Scientific reports","confidence":"High","confidence_rationale":"Tier 2 — clean KO with multiple orthogonal readouts (behavior, ultrastructure, cilia beat), defines functional role in ependymal cilia motility","pmids":["32709945"],"is_preprint":false},{"year":2016,"finding":"Zebrafish Rsph9 localizes to both 9+2 and 9+0 ciliary axonemes; CRISPR-mediated rsph9 mutation impairs motility of olfactory (9+2) cilia and 9+0 neural cilia, and compromises structural integrity of both axoneme types; rsph9 mutants show reduced acoustic startle response consistent with hearing impairment, revealing a role in kinocilia of the inner ear.","method":"CRISPR mutagenesis in zebrafish, fluorescence microscopy (axonemal localization), behavioral assays (acoustic startle response)","journal":"Scientific reports","confidence":"High","confidence_rationale":"Tier 2 — CRISPR loss-of-function with multiple orthogonal phenotypic readouts (structural, motility, behavioral) in an established vertebrate model","pmids":["27687975"],"is_preprint":false},{"year":2023,"finding":"LRRC23 (an RS3 head component) directly interacts with RSPH9 via its C-terminus; C-terminal truncation of LRRC23 abolishes this interaction; cryo-electron tomography of LRRC23 mutant spermatozoa shows absence of RS3 head and sperm-specific RS2-RS3 bridge, placing RSPH9 as a binding partner at the RS3 head.","method":"Purified recombinant protein interaction assay (pulldown), cryo-electron tomography, mutant mouse model","journal":"eLife","confidence":"High","confidence_rationale":"Tier 1 — recombinant protein interaction with mutagenesis validation + cryo-ET structural evidence in a single study","pmids":["38091523"],"is_preprint":false},{"year":2023,"finding":"Pathogenic variants in RSPH9 cause male infertility due to sperm cell dysmotility and abnormal flagellar RSPH9 protein composition, as demonstrated by immunofluorescence microscopy on sperm flagella of affected individuals.","method":"Next-generation sequencing, immunofluorescence microscopy on sperm flagella, high-speed video microscopy, TEM, semen analysis","journal":"Frontiers in genetics","confidence":"Medium","confidence_rationale":"Tier 2 — human patient study with multiple diagnostic methods establishing direct link between RSPH9 loss and sperm dysmotility","pmids":["36873931"],"is_preprint":false},{"year":2022,"finding":"SPEF2 interacts with RSPH9 in vitro, suggesting SPEF2 and RSPH9 function together in flagellar assembly.","method":"Co-immunoprecipitation/pulldown in vitro interaction assay, proteomic analysis of SPEF2-mutant spermatozoa","journal":"Asian journal of andrology","confidence":"Low","confidence_rationale":"Tier 3 — single in vitro interaction assay, single lab, no functional mutagenesis follow-up","pmids":["34755699"],"is_preprint":false},{"year":2025,"finding":"RSPH9 is identified as a component of the radial spoke 1 (RS1) head in human and mouse sperm flagella; IQUB deficiency causes RS1-specific deficiency without affecting RS2 or RS3, and RSPH9 along with RSPH3, RSPH6A, and DYDC1 constitute the RS1 head.","method":"Protein mass spectrometry, western blotting, bioinformatic analysis, Iqub-/- mouse model, TEM","journal":"Cell communication and signaling","confidence":"Medium","confidence_rationale":"Tier 2 — mass spectrometry with KO mouse validation defines RSPH9 as RS1 head component, single lab","pmids":["39849482"],"is_preprint":false},{"year":2024,"finding":"DNAH12 interacts with radial spoke head proteins RSPH1, RSPH9, and DNAJB13 to regulate central pair stability in sperm flagella; DNAH12 deficiency causes central pair loss in sperm but not in cilia.","method":"Co-immunoprecipitation, Dnah12-/- and Dnah12mut/mut mouse models, TEM, immunofluorescence","journal":"bioRxiv (preprint)","confidence":"Medium","confidence_rationale":"Tier 2 — Co-IP interaction plus KO mouse model with TEM ultrastructural readout, preprint not yet peer-reviewed","pmids":["bio_10.1101_2024.06.20.599934"],"is_preprint":true},{"year":2017,"finding":"RSPH9 is one of the most abundant non-tubulin proteins in human airway cilia axonemes (1850 fmol), establishing it as a major structural constituent of the ciliary axoneme.","method":"Label-free LC/MSE quantitative proteomics of human airway cilia axonemes with absolute quantification","journal":"Journal of proteome research","confidence":"Medium","confidence_rationale":"Tier 2 — quantitative mass spectrometry with absolute quantification, defines RSPH9 as high-abundance axonemal component","pmids":["28282151"],"is_preprint":false}],"current_model":"RSPH9 is a high-abundance structural component of the radial spoke head in motile cilia and sperm flagella axonemes, where it functions downstream of RSPH4A (the core spoke head protein) and RSPH1 in a hierarchical assembly pathway; loss of RSPH9 destabilizes the central pair apparatus, converts the ciliary beat from planar to rotational, and causes primary ciliary dyskinesia with central-pair abnormalities, hydrocephalus, and male infertility, while its C-terminal domain physically interacts with the RS3 head protein LRRC23 and its stability in the axoneme depends on RSPH6A."},"narrative":{"teleology":[{"year":2009,"claim":"Establishing RSPH9 as a radial spoke head gene whose mutations cause primary ciliary dyskinesia answered the fundamental question of whether radial spoke head defects in humans produce a PCD phenotype with central pair abnormalities.","evidence":"Positional cloning in consanguineous families, zebrafish knockdown/rescue, and Chlamydomonas knockdown","pmids":["19200523"],"confidence":"High","gaps":["Precise position of RSPH9 within the spoke head architecture unknown","Assembly hierarchy relative to other spoke head proteins not defined","Mechanism linking spoke head loss to central pair destabilization unresolved"]},{"year":2014,"claim":"Demonstrating that RSPH1 mutations cause co-loss of RSPH4A and RSPH9 established that the spoke head proteins are interdependent and that spoke head integrity is required for central pair stability.","evidence":"Targeted NGS, TEM, and high-resolution immunofluorescence of patient respiratory cilia","pmids":["24518672"],"confidence":"High","gaps":["Direction of dependency (which protein recruits which) not resolved by co-loss data alone","Whether RSPH9 loss is a cause or consequence of spoke head disassembly unclear"]},{"year":2015,"claim":"Systematic immunofluorescence across RSPH9, RSPH4A, and RSPH1 patient genotypes resolved the assembly hierarchy, placing RSPH9 as the most downstream component that depends on both RSPH4A and RSPH1 for axonemal incorporation.","evidence":"Reciprocal high-resolution immunofluorescence across 16 families with defined biallelic mutations","pmids":["25789548"],"confidence":"High","gaps":["Direct protein-protein interactions mediating this hierarchy not demonstrated biochemically","Whether RSPH9 has any autonomous structural role outside the spoke head unknown"]},{"year":2016,"claim":"Demonstrating that RSPH9 localizes to both 9+2 and 9+0 axonemes and is required for structural integrity of both expanded RSPH9's role beyond canonical motile cilia to include non-canonical 9+0 cilia and kinocilia.","evidence":"CRISPR mutagenesis in zebrafish with fluorescence microscopy and acoustic startle behavioral assays","pmids":["27687975"],"confidence":"High","gaps":["Structural role of RSPH9 in 9+0 cilia that lack a canonical central pair unexplained","Mechanism of hearing impairment in rsph9 mutants not fully elucidated"]},{"year":2017,"claim":"Quantitative proteomics established RSPH9 as one of the most abundant non-tubulin proteins in human airway cilia axonemes, confirming it is a major structural constituent rather than a regulatory factor.","evidence":"Label-free LC/MSE absolute quantitative proteomics of human airway cilia","pmids":["28282151"],"confidence":"Medium","gaps":["Stoichiometry relative to other spoke head subunits not precisely determined","Whether abundance varies across tissue-specific cilia not addressed"]},{"year":2018,"claim":"RNAi depletion of Rsph9 in mammalian ependymal cilia directly demonstrated that RSPH9 is required for central pair maintenance and planar beat pattern, converting beat motion from planar to rotational upon loss.","evidence":"RNAi knockdown in mouse ependymal cilia with high-speed video microscopy, TEM, and immunofluorescence","pmids":["30383886"],"confidence":"High","gaps":["Molecular mechanism by which spoke head loss destabilizes the central pair not resolved","Whether rotational beat is the default state in absence of radial spoke constraint untested"]},{"year":2018,"claim":"Finding that RSPH9 disappears from sperm flagella in Rsph6a knockout mice established that RSPH9 axonemal stability depends on RSPH6A, identifying an additional dependency in the sperm-specific spoke head.","evidence":"Rsph6a knockout mouse model with immunofluorescence of sperm flagella","pmids":["30185526"],"confidence":"Medium","gaps":["Whether RSPH6A directly binds RSPH9 or acts indirectly not determined","Whether this dependency operates in respiratory cilia not tested"]},{"year":2020,"claim":"Rsph9 knockout mice developed neonatal hydrocephalus with altered ependymal cilia beating, establishing the in vivo physiological consequence of complete RSPH9 loss in mammals.","evidence":"Rsph9 knockout mouse with high-speed video microscopy, TEM, and immunofluorescence","pmids":["32709945"],"confidence":"High","gaps":["Contribution of RSPH9 loss to situs defects not observed or addressed in this model","Whether hydrocephalus arises purely from reduced CSF flow or has additional components unknown"]},{"year":2023,"claim":"Demonstration that LRRC23 directly binds RSPH9 via its C-terminus and that LRRC23 loss ablates the RS3 head placed RSPH9 as a direct physical partner at the RS3 head structure, providing the first biochemically defined interaction for RSPH9.","evidence":"Recombinant protein pulldown with truncation mutants and cryo-electron tomography of LRRC23 mutant sperm","pmids":["38091523"],"confidence":"High","gaps":["Full atomic-resolution structure of RSPH9 within the spoke head not available","Whether RSPH9 bridges RS3 to additional spoke components not tested"]},{"year":2023,"claim":"Identification of RSPH9 pathogenic variants causing isolated male infertility with sperm dysmotility extended the disease spectrum of RSPH9 deficiency beyond respiratory PCD.","evidence":"NGS, immunofluorescence on sperm flagella, high-speed video microscopy, TEM, semen analysis in affected individuals","pmids":["36873931"],"confidence":"Medium","gaps":["Genotype-phenotype correlation for specific RSPH9 variants incompletely characterized","Whether partial RSPH9 loss can produce isolated infertility without respiratory phenotype needs larger cohorts"]},{"year":2025,"claim":"Mass spectrometry and IQUB knockout analysis identified RSPH9 as a component of the RS1 head in sperm flagella, establishing that RSPH9 is shared across multiple radial spoke subtypes (RS1 and RS3).","evidence":"Protein mass spectrometry, western blotting, and Iqub knockout mouse model with TEM","pmids":["39849482"],"confidence":"Medium","gaps":["Whether RSPH9 has identical or distinct roles in RS1 versus RS3 heads not resolved","Stoichiometry of RSPH9 across RS subtypes unknown"]},{"year":null,"claim":"The atomic-resolution structure of RSPH9 within the radial spoke head, the mechanism by which spoke head integrity stabilizes the central pair apparatus, and the basis for tissue-specific differences in RSPH9 dependency (cilia vs. flagella) remain unresolved.","evidence":"","pmids":[],"confidence":"High","gaps":["No high-resolution structure of RSPH9 or its spoke head complex available","Mechanism of central pair destabilization upon spoke head loss is unknown","Tissue-specific regulatory differences between cilia and sperm flagella unexplained"]}],"mechanism_profile":{"molecular_activity":[{"term_id":"GO:0005198","term_label":"structural molecule activity","supporting_discovery_ids":[0,1,3,5,12]}],"localization":[{"term_id":"GO:0005929","term_label":"cilium","supporting_discovery_ids":[0,1,2,3,5,6,12]},{"term_id":"GO:0005856","term_label":"cytoskeleton","supporting_discovery_ids":[0,3,7,10]}],"pathway":[{"term_id":"R-HSA-1852241","term_label":"Organelle biogenesis and maintenance","supporting_discovery_ids":[0,1,3,5,7]}],"complexes":["Radial spoke head (RS1 head)","Radial spoke head (RS3 head)"],"partners":["RSPH4A","RSPH1","RSPH6A","LRRC23","RSPH3","SPEF2"],"other_free_text":[]},"mechanistic_narrative":"RSPH9 is a high-abundance structural protein of the radial spoke head in motile cilia and sperm flagella, essential for central pair microtubule stability and planar ciliary beat pattern. Within the radial spoke head assembly hierarchy, RSPH9 acts downstream of both RSPH4A and RSPH1: loss of RSPH4A or RSPH1 eliminates axonemal RSPH9, whereas RSPH9 mutations do not affect RSPH4A or RSPH1 localization [PMID:25789548]. RSPH9 physically interacts with the RS3 head protein LRRC23 via its C-terminus and is a component of both RS1 and RS3 head structures; its depletion converts the ciliary beat from planar to rotational, causes near-complete central pair loss, and in mice produces neonatal hydrocephalus [PMID:30383886, PMID:32709945, PMID:38091523]. Loss-of-function mutations in RSPH9 cause primary ciliary dyskinesia with central-pair abnormalities and male infertility due to sperm dysmotility [PMID:19200523, PMID:36873931]."},"prefetch_data":{"uniprot":{"accession":"Q9H1X1","full_name":"Radial spoke head protein 9 homolog","aliases":[],"length_aa":276,"mass_kda":31.3,"function":"Functions as part of axonemal radial spoke complexes that play an important part in the motility of sperm and cilia (PubMed:19200523). Essential for both the radial spoke head assembly and the central pair microtubule stability in ependymal motile cilia (By similarity). Required for motility of olfactory and neural cilia and for the structural integrity of ciliary axonemes in both 9+0 and 9+2 motile cilia (By similarity)","subcellular_location":"Cytoplasm, cytoskeleton, cilium axoneme; Cytoplasm, cytoskeleton, flagellum axoneme; Cell projection, kinocilium","url":"https://www.uniprot.org/uniprotkb/Q9H1X1/entry"},"depmap":{"release":"DepMap","has_data":true,"is_common_essential":false,"resolved_as":"","url":"https://depmap.org/portal/gene/RSPH9","classification":"Not Classified","n_dependent_lines":76,"n_total_lines":1208,"dependency_fraction":0.06291390728476821},"opencell":{"profiled":false,"resolved_as":"","ensg_id":"","cell_line_id":"","localizations":[],"interactors":[],"url":"https://opencell.sf.czbiohub.org/search/RSPH9","total_profiled":1310},"omim":[{"mim_id":"620848","title":"SPERMATOGENIC FAILURE 92; SPGF92","url":"https://www.omim.org/entry/620848"},{"mim_id":"620708","title":"LEUCINE-RICH REPEAT-CONTAINING PROTEIN 23; LRRC23","url":"https://www.omim.org/entry/620708"},{"mim_id":"616481","title":"CILIARY DYSKINESIA, PRIMARY, 32; CILD32","url":"https://www.omim.org/entry/616481"},{"mim_id":"615876","title":"RADIAL SPOKE HEAD 3; RSPH3","url":"https://www.omim.org/entry/615876"},{"mim_id":"612650","title":"CILIARY DYSKINESIA, PRIMARY, 12; CILD12","url":"https://www.omim.org/entry/612650"}],"hpa":{"profiled":true,"resolved_as":"","reliability":"Approved","locations":[{"location":"Mid piece","reliability":"Approved"},{"location":"Principal piece","reliability":"Approved"},{"location":"End piece","reliability":"Approved"},{"location":"Acrosome","reliability":"Additional"},{"location":"Equatorial segment","reliability":"Additional"}],"tissue_specificity":"Tissue enhanced","tissue_distribution":"Detected in some","driving_tissues":[{"tissue":"choroid plexus","ntpm":8.1},{"tissue":"fallopian tube","ntpm":7.8},{"tissue":"testis","ntpm":14.5}],"url":"https://www.proteinatlas.org/search/RSPH9"},"hgnc":{"alias_symbol":["FLJ30845","CILD12"],"prev_symbol":["MRPS18AL1","C6orf206"]},"alphafold":{"accession":"Q9H1X1","domains":[{"cath_id":"-","chopping":"4-275","consensus_level":"medium","plddt":91.5623,"start":4,"end":275}],"viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9H1X1","model_url":"https://alphafold.ebi.ac.uk/files/AF-Q9H1X1-F1-model_v6.cif","pae_url":"https://alphafold.ebi.ac.uk/files/AF-Q9H1X1-F1-predicted_aligned_error_v6.png","plddt_mean":91.88},"mouse_models":{"mgi_url":"https://www.informatics.jax.org/marker/summary?nomen=RSPH9","jax_strain_url":"https://www.jax.org/strain/search?query=RSPH9"},"sequence":{"accession":"Q9H1X1","fasta_url":"https://rest.uniprot.org/uniprotkb/Q9H1X1.fasta","uniprot_url":"https://www.uniprot.org/uniprotkb/Q9H1X1/entry","alphafold_viewer_url":"https://alphafold.ebi.ac.uk/entry/Q9H1X1"}},"corpus_meta":[{"pmid":"19200523","id":"PMC_19200523","title":"Mutations in radial spoke head protein genes RSPH9 and RSPH4A cause primary ciliary dyskinesia with central-microtubular-pair abnormalities.","date":"2009","source":"American journal of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/19200523","citation_count":267,"is_preprint":false},{"pmid":"25789548","id":"PMC_25789548","title":"Immunofluorescence Analysis and Diagnosis of Primary Ciliary Dyskinesia with Radial Spoke Defects.","date":"2015","source":"American journal of respiratory cell and molecular biology","url":"https://pubmed.ncbi.nlm.nih.gov/25789548","citation_count":104,"is_preprint":false},{"pmid":"30185526","id":"PMC_30185526","title":"RSPH6A is required for sperm flagellum formation and male fertility in mice.","date":"2018","source":"Journal of cell science","url":"https://pubmed.ncbi.nlm.nih.gov/30185526","citation_count":86,"is_preprint":false},{"pmid":"24518672","id":"PMC_24518672","title":"Targeted NGS gene panel identifies mutations in RSPH1 causing primary ciliary dyskinesia and a common mechanism for ciliary central pair agenesis due to radial spoke defects.","date":"2014","source":"Human molecular genetics","url":"https://pubmed.ncbi.nlm.nih.gov/24518672","citation_count":76,"is_preprint":false},{"pmid":"28282151","id":"PMC_28282151","title":"Quantitative Proteomic Analysis of Human Airway Cilia Identifies Previously Uncharacterized Proteins of High Abundance.","date":"2017","source":"Journal of proteome research","url":"https://pubmed.ncbi.nlm.nih.gov/28282151","citation_count":69,"is_preprint":false},{"pmid":"33577779","id":"PMC_33577779","title":"Clinical and Genetic Spectrum of Children With Primary Ciliary Dyskinesia in China.","date":"2021","source":"Chest","url":"https://pubmed.ncbi.nlm.nih.gov/33577779","citation_count":64,"is_preprint":false},{"pmid":"26883180","id":"PMC_26883180","title":"Genome-wide DNA methylation analysis in hepatocellular carcinoma.","date":"2016","source":"Oncology reports","url":"https://pubmed.ncbi.nlm.nih.gov/26883180","citation_count":49,"is_preprint":false},{"pmid":"30935420","id":"PMC_30935420","title":"Bioinformatic identification of candidate biomarkers and related transcription factors in nasopharyngeal carcinoma.","date":"2019","source":"World journal of surgical oncology","url":"https://pubmed.ncbi.nlm.nih.gov/30935420","citation_count":41,"is_preprint":false},{"pmid":"31886214","id":"PMC_31886214","title":"A Six-Gene Signature Predicts Survival of Adenocarcinoma Type of Non-Small-Cell Lung Cancer Patients: A Comprehensive Study Based on Integrated Analysis and Weighted Gene Coexpression Network.","date":"2019","source":"BioMed research international","url":"https://pubmed.ncbi.nlm.nih.gov/31886214","citation_count":28,"is_preprint":false},{"pmid":"25575132","id":"PMC_25575132","title":"High-resolution genomic analysis does not qualify atypical plexus papilloma as a separate entity among choroid plexus tumors.","date":"2015","source":"Journal of neuropathology and experimental neurology","url":"https://pubmed.ncbi.nlm.nih.gov/25575132","citation_count":27,"is_preprint":false},{"pmid":"36873931","id":"PMC_36873931","title":"Pathogenic gene variants in CCDC39, CCDC40, RSPH1, RSPH9, HYDIN, and SPEF2 cause defects of sperm flagella composition and male infertility.","date":"2023","source":"Frontiers in genetics","url":"https://pubmed.ncbi.nlm.nih.gov/36873931","citation_count":24,"is_preprint":false},{"pmid":"31285900","id":"PMC_31285900","title":"Wide phenotypic variability in RSPH9-associated primary ciliary dyskinesia: review of a case-series from Cyprus.","date":"2019","source":"Journal of thoracic disease","url":"https://pubmed.ncbi.nlm.nih.gov/31285900","citation_count":23,"is_preprint":false},{"pmid":"32709945","id":"PMC_32709945","title":"Loss of Rsph9 causes neonatal hydrocephalus with abnormal development of motile cilia in mice.","date":"2020","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/32709945","citation_count":19,"is_preprint":false},{"pmid":"34755699","id":"PMC_34755699","title":"Sperm flagellar 2 (SPEF2) is essential for sperm flagellar assembly in humans.","date":"2022","source":"Asian journal of andrology","url":"https://pubmed.ncbi.nlm.nih.gov/34755699","citation_count":18,"is_preprint":false},{"pmid":"33182294","id":"PMC_33182294","title":"Immunofluorescence Analysis as a Diagnostic Tool in a Spanish Cohort of Patients with Suspected Primary Ciliary Dyskinesia.","date":"2020","source":"Journal of clinical medicine","url":"https://pubmed.ncbi.nlm.nih.gov/33182294","citation_count":18,"is_preprint":false},{"pmid":"20070851","id":"PMC_20070851","title":"Founder mutation(s) in the RSPH9 gene leading to primary ciliary dyskinesia in two inbred Bedouin families.","date":"2010","source":"Annals of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/20070851","citation_count":17,"is_preprint":false},{"pmid":"30383886","id":"PMC_30383886","title":"Rsph9 is critical for ciliary radial spoke assembly and central pair microtubule stability.","date":"2018","source":"Biology of the cell","url":"https://pubmed.ncbi.nlm.nih.gov/30383886","citation_count":17,"is_preprint":false},{"pmid":"27687975","id":"PMC_27687975","title":"Novel roles for the radial spoke head protein 9 in neural and neurosensory cilia.","date":"2016","source":"Scientific reports","url":"https://pubmed.ncbi.nlm.nih.gov/27687975","citation_count":15,"is_preprint":false},{"pmid":"38091523","id":"PMC_38091523","title":"LRRC23 truncation impairs radial spoke 3 head assembly and sperm motility underlying male infertility.","date":"2023","source":"eLife","url":"https://pubmed.ncbi.nlm.nih.gov/38091523","citation_count":14,"is_preprint":false},{"pmid":"35046476","id":"PMC_35046476","title":"Combining RSPH9 founder mutation screening and next-generation sequencing analysis is efficient for primary ciliary dyskinesia diagnosis in Saudi patients.","date":"2022","source":"Journal of human genetics","url":"https://pubmed.ncbi.nlm.nih.gov/35046476","citation_count":7,"is_preprint":false},{"pmid":"31798623","id":"PMC_31798623","title":"An Integrated Analysis of Radial Spoke Head and Outer Dynein Arm Protein Defects and Ciliogenesis Abnormality in Nasal Polyps.","date":"2019","source":"Frontiers in genetics","url":"https://pubmed.ncbi.nlm.nih.gov/31798623","citation_count":7,"is_preprint":false},{"pmid":"34401452","id":"PMC_34401452","title":"Clinical and molecular characteristics of primary ciliary dyskinesia: A tertiary care centre experience.","date":"2021","source":"International journal of pediatrics & adolescent medicine","url":"https://pubmed.ncbi.nlm.nih.gov/34401452","citation_count":7,"is_preprint":false},{"pmid":"36435264","id":"PMC_36435264","title":"Motile Ciliary Disorders of the Nasal Epithelium in Adults With Bronchiectasis.","date":"2022","source":"Chest","url":"https://pubmed.ncbi.nlm.nih.gov/36435264","citation_count":6,"is_preprint":false},{"pmid":"37892347","id":"PMC_37892347","title":"Clinical and Genetic Characterization of Patients with Primary Ciliary Dyskinesia in Southwest Saudi Arabia: A Cross Sectional Study.","date":"2023","source":"Children (Basel, Switzerland)","url":"https://pubmed.ncbi.nlm.nih.gov/37892347","citation_count":6,"is_preprint":false},{"pmid":"39849482","id":"PMC_39849482","title":"IQUB mutation induces radial spoke 1 deficiency causing asthenozoospermia with normal sperm morphology in humans and mice.","date":"2025","source":"Cell communication and signaling : CCS","url":"https://pubmed.ncbi.nlm.nih.gov/39849482","citation_count":5,"is_preprint":false},{"pmid":"38359560","id":"PMC_38359560","title":"Application of sperm motion kinematics and motility-related proteins for prediction of male fertility.","date":"2024","source":"Theriogenology","url":"https://pubmed.ncbi.nlm.nih.gov/38359560","citation_count":5,"is_preprint":false},{"pmid":"33793549","id":"PMC_33793549","title":"alms1 mutant zebrafish do not show hair cell phenotypes seen in other cilia mutants.","date":"2021","source":"PloS one","url":"https://pubmed.ncbi.nlm.nih.gov/33793549","citation_count":3,"is_preprint":false},{"pmid":"36865175","id":"PMC_36865175","title":"LRRC23 truncation impairs radial spoke 3 head assembly and sperm motility underlying male infertility.","date":"2023","source":"bioRxiv : the preprint server for biology","url":"https://pubmed.ncbi.nlm.nih.gov/36865175","citation_count":3,"is_preprint":false},{"pmid":"33851733","id":"PMC_33851733","title":"Severe herpes virus 6 interstitial pneumonia in an infant with three variants in genes predisposing to lung disease.","date":"2021","source":"Journal of medical virology","url":"https://pubmed.ncbi.nlm.nih.gov/33851733","citation_count":3,"is_preprint":false},{"pmid":"37892643","id":"PMC_37892643","title":"Mapping the Most Common Founder Variant in RSPH9 That Causes Primary Ciliary Dyskinesia in Multiple Consanguineous Families of Bedouin Arabs.","date":"2023","source":"Journal of clinical medicine","url":"https://pubmed.ncbi.nlm.nih.gov/37892643","citation_count":2,"is_preprint":false},{"pmid":"39352166","id":"PMC_39352166","title":"Exploring nasopharyngeal carcinoma genetics: Bioinformatics insights into pathways and gene associations.","date":"2024","source":"The Medical journal of Malaysia","url":"https://pubmed.ncbi.nlm.nih.gov/39352166","citation_count":2,"is_preprint":false},{"pmid":"37351244","id":"PMC_37351244","title":"Primary Ciliary Dyskinesia and Type 1 Diabetes: True Association or Circumstantial?","date":"2023","source":"Cureus","url":"https://pubmed.ncbi.nlm.nih.gov/37351244","citation_count":1,"is_preprint":false},{"pmid":"36820148","id":"PMC_36820148","title":"An Integrated Analysis Reveals Ciliary Abnormalities in Antrochoanal Polyps.","date":"2023","source":"Journal of inflammation research","url":"https://pubmed.ncbi.nlm.nih.gov/36820148","citation_count":1,"is_preprint":false},{"pmid":"41267578","id":"PMC_41267578","title":"Prevalence and Nationality Distribution of Known and Novel Genetic Variants in Children With Primary Ciliary Dyskinesia in the State of Qatar.","date":"2025","source":"Clinical genetics","url":"https://pubmed.ncbi.nlm.nih.gov/41267578","citation_count":0,"is_preprint":false},{"pmid":"41571964","id":"PMC_41571964","title":"Associations of air pollution and genetic risk and their interaction with risk of Alzheimer's disease: identification of risk loci and potential biological pathways.","date":"2026","source":"GeroScience","url":"https://pubmed.ncbi.nlm.nih.gov/41571964","citation_count":0,"is_preprint":false},{"pmid":"36059358","id":"PMC_36059358","title":"An Unusual Cause of Respiratory Distress in Term Neonate.","date":"2022","source":"Cureus","url":"https://pubmed.ncbi.nlm.nih.gov/36059358","citation_count":0,"is_preprint":false},{"pmid":null,"id":"bio_10.1101_2024.06.20.599934","title":"Deficiency in DNAH12 causes male infertility by impairing DNAH1 and DNALI1 recruitment in humans and mice","date":"2024-06-23","source":"bioRxiv","url":"https://doi.org/10.1101/2024.06.20.599934","citation_count":0,"is_preprint":true}],"cost":{"stage1":{"model":"claude-sonnet-4-6","input_tokens":21366,"output_tokens":3100,"usd":0.055299},"stage2":{"model":"claude-opus-4-6","input_tokens":6461,"output_tokens":2663,"usd":0.14832},"total_usd":0.203619,"stage1_batch_id":"msgbatch_011rkcQdVV1RaFq9XhcG6df6","stage2_batch_id":"msgbatch_01RzgrJafdF4EWHhj5mNi6dh","note":"batch pricing = 50% of standard"},"stage1_raw":"```json\n{\n  \"discoveries\": [\n    {\n      \"year\": 2009,\n      \"finding\": \"RSPH9 encodes a protein component of the axonemal radial spoke head; mutations cause primary ciliary dyskinesia with central-microtubular-pair abnormalities; knockdown of RSPH9 orthologs in zebrafish and Chlamydomonas disrupts normal motile cilia movement, and reintroduction of gene expression restores normal beat pattern in zebrafish.\",\n      \"method\": \"Genetic linkage analysis, positional cloning, in situ hybridization (murine Rsph9), zebrafish knockdown/rescue, Chlamydomonas knockdown\",\n      \"journal\": \"American journal of human genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods (genetics, in situ hybridization, zebrafish knockdown+rescue, Chlamydomonas), replicated in two model organisms, highly cited foundational paper\",\n      \"pmids\": [\"19200523\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2015,\n      \"finding\": \"RSPH4A is the core protein of the radial spoke head; absence of RSPH4A (due to RSPH4A mutations) results in deficient axonemal assembly of both RSPH1 and RSPH9; RSPH1 mutations cause loss of RSPH9 from the axoneme; RSPH9 mutations result in absence of RSPH9 but do not affect axonemal assembly of RSPH1 or RSPH4A, placing RSPH9 downstream of both RSPH4A and RSPH1 in radial spoke head assembly.\",\n      \"method\": \"High-resolution immunofluorescence analysis of human respiratory cilia from patients with defined biallelic mutations in RSPH9, RSPH4A, and RSPH1\",\n      \"journal\": \"American journal of respiratory cell and molecular biology\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — reciprocal immunofluorescence across multiple patient genotypes defining assembly hierarchy, replicated across 16 families, highly cited\",\n      \"pmids\": [\"25789548\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2014,\n      \"finding\": \"RSPH1, RSPH4A, and RSPH9 are all components of the 'head' structure of ciliary radial spoke complexes; high-resolution immunofluorescence showed loss of RSPH4A and RSPH9 along with RSPH1 from RSPH1-mutated cilia, suggesting RSPH1 mutations may result in loss of the entire spoke head structure; proposed mechanism: CP loss arises from instability due to loss of normal radial spoke head tethering.\",\n      \"method\": \"Targeted NGS gene panel sequencing, ultrastructural analysis by TEM, high-resolution immunofluorescence of patient cilia\",\n      \"journal\": \"Human molecular genetics\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — multiple orthogonal methods (genetics, TEM, immunofluorescence), defines epistatic relationship in spoke head assembly\",\n      \"pmids\": [\"24518672\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"Mouse Rsph9 is essential for both radial spoke head assembly and central pair microtubule maintenance in ependymal motile cilia; RNAi depletion of Rsph9 in mouse ependymal cilia caused near-complete central pair loss, altered beat pattern from planar to rotational, and marked downregulation of multiple radial spoke proteins including those in the head.\",\n      \"method\": \"RNAi knockdown in mouse ependymal cilia, high-speed video microscopy, immunofluorescence, TEM\",\n      \"journal\": \"Biology of the cell\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — clean RNAi KD with multiple orthogonal readouts (beat pattern, ultrastructure, protein localization) in mammalian cells\",\n      \"pmids\": [\"30383886\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2018,\n      \"finding\": \"RSPH9 is required for RSPH6A-dependent flagellar assembly; in Rsph6a knockout mice, RSPH9 disappears from sperm flagella, indicating RSPH9 stability/localization depends on RSPH6A.\",\n      \"method\": \"Rsph6a knockout mouse model, immunofluorescence of sperm flagella\",\n      \"journal\": \"Journal of cell science\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — clean KO with defined molecular phenotype (loss of RSPH9 localization), single lab\",\n      \"pmids\": [\"30185526\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2020,\n      \"finding\": \"Deletion of Rsph9 in mice leads to neonatal hydrocephalus; Rsph9-/- ependymal cilia show lower beating amplitude and irregular rotational beating pattern, increased centriolar patch size, and frequent abnormal ectopic ciliary membrane inclusions, while overall axonemal organization is largely preserved.\",\n      \"method\": \"Rsph9 knockout mouse model, high-speed video microscopy, TEM, immunofluorescence\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — clean KO with multiple orthogonal readouts (behavior, ultrastructure, cilia beat), defines functional role in ependymal cilia motility\",\n      \"pmids\": [\"32709945\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2016,\n      \"finding\": \"Zebrafish Rsph9 localizes to both 9+2 and 9+0 ciliary axonemes; CRISPR-mediated rsph9 mutation impairs motility of olfactory (9+2) cilia and 9+0 neural cilia, and compromises structural integrity of both axoneme types; rsph9 mutants show reduced acoustic startle response consistent with hearing impairment, revealing a role in kinocilia of the inner ear.\",\n      \"method\": \"CRISPR mutagenesis in zebrafish, fluorescence microscopy (axonemal localization), behavioral assays (acoustic startle response)\",\n      \"journal\": \"Scientific reports\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 2 — CRISPR loss-of-function with multiple orthogonal phenotypic readouts (structural, motility, behavioral) in an established vertebrate model\",\n      \"pmids\": [\"27687975\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"LRRC23 (an RS3 head component) directly interacts with RSPH9 via its C-terminus; C-terminal truncation of LRRC23 abolishes this interaction; cryo-electron tomography of LRRC23 mutant spermatozoa shows absence of RS3 head and sperm-specific RS2-RS3 bridge, placing RSPH9 as a binding partner at the RS3 head.\",\n      \"method\": \"Purified recombinant protein interaction assay (pulldown), cryo-electron tomography, mutant mouse model\",\n      \"journal\": \"eLife\",\n      \"confidence\": \"High\",\n      \"confidence_rationale\": \"Tier 1 — recombinant protein interaction with mutagenesis validation + cryo-ET structural evidence in a single study\",\n      \"pmids\": [\"38091523\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2023,\n      \"finding\": \"Pathogenic variants in RSPH9 cause male infertility due to sperm cell dysmotility and abnormal flagellar RSPH9 protein composition, as demonstrated by immunofluorescence microscopy on sperm flagella of affected individuals.\",\n      \"method\": \"Next-generation sequencing, immunofluorescence microscopy on sperm flagella, high-speed video microscopy, TEM, semen analysis\",\n      \"journal\": \"Frontiers in genetics\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — human patient study with multiple diagnostic methods establishing direct link between RSPH9 loss and sperm dysmotility\",\n      \"pmids\": [\"36873931\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2022,\n      \"finding\": \"SPEF2 interacts with RSPH9 in vitro, suggesting SPEF2 and RSPH9 function together in flagellar assembly.\",\n      \"method\": \"Co-immunoprecipitation/pulldown in vitro interaction assay, proteomic analysis of SPEF2-mutant spermatozoa\",\n      \"journal\": \"Asian journal of andrology\",\n      \"confidence\": \"Low\",\n      \"confidence_rationale\": \"Tier 3 — single in vitro interaction assay, single lab, no functional mutagenesis follow-up\",\n      \"pmids\": [\"34755699\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2025,\n      \"finding\": \"RSPH9 is identified as a component of the radial spoke 1 (RS1) head in human and mouse sperm flagella; IQUB deficiency causes RS1-specific deficiency without affecting RS2 or RS3, and RSPH9 along with RSPH3, RSPH6A, and DYDC1 constitute the RS1 head.\",\n      \"method\": \"Protein mass spectrometry, western blotting, bioinformatic analysis, Iqub-/- mouse model, TEM\",\n      \"journal\": \"Cell communication and signaling\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — mass spectrometry with KO mouse validation defines RSPH9 as RS1 head component, single lab\",\n      \"pmids\": [\"39849482\"],\n      \"is_preprint\": false\n    },\n    {\n      \"year\": 2024,\n      \"finding\": \"DNAH12 interacts with radial spoke head proteins RSPH1, RSPH9, and DNAJB13 to regulate central pair stability in sperm flagella; DNAH12 deficiency causes central pair loss in sperm but not in cilia.\",\n      \"method\": \"Co-immunoprecipitation, Dnah12-/- and Dnah12mut/mut mouse models, TEM, immunofluorescence\",\n      \"journal\": \"bioRxiv (preprint)\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — Co-IP interaction plus KO mouse model with TEM ultrastructural readout, preprint not yet peer-reviewed\",\n      \"pmids\": [\"bio_10.1101_2024.06.20.599934\"],\n      \"is_preprint\": true\n    },\n    {\n      \"year\": 2017,\n      \"finding\": \"RSPH9 is one of the most abundant non-tubulin proteins in human airway cilia axonemes (1850 fmol), establishing it as a major structural constituent of the ciliary axoneme.\",\n      \"method\": \"Label-free LC/MSE quantitative proteomics of human airway cilia axonemes with absolute quantification\",\n      \"journal\": \"Journal of proteome research\",\n      \"confidence\": \"Medium\",\n      \"confidence_rationale\": \"Tier 2 — quantitative mass spectrometry with absolute quantification, defines RSPH9 as high-abundance axonemal component\",\n      \"pmids\": [\"28282151\"],\n      \"is_preprint\": false\n    }\n  ],\n  \"current_model\": \"RSPH9 is a high-abundance structural component of the radial spoke head in motile cilia and sperm flagella axonemes, where it functions downstream of RSPH4A (the core spoke head protein) and RSPH1 in a hierarchical assembly pathway; loss of RSPH9 destabilizes the central pair apparatus, converts the ciliary beat from planar to rotational, and causes primary ciliary dyskinesia with central-pair abnormalities, hydrocephalus, and male infertility, while its C-terminal domain physically interacts with the RS3 head protein LRRC23 and its stability in the axoneme depends on RSPH6A.\"\n}\n```","stage2_raw":"```json\n{\n  \"mechanistic_narrative\": \"RSPH9 is a high-abundance structural protein of the radial spoke head in motile cilia and sperm flagella, essential for central pair microtubule stability and planar ciliary beat pattern. Within the radial spoke head assembly hierarchy, RSPH9 acts downstream of both RSPH4A and RSPH1: loss of RSPH4A or RSPH1 eliminates axonemal RSPH9, whereas RSPH9 mutations do not affect RSPH4A or RSPH1 localization [PMID:25789548]. RSPH9 physically interacts with the RS3 head protein LRRC23 via its C-terminus and is a component of both RS1 and RS3 head structures; its depletion converts the ciliary beat from planar to rotational, causes near-complete central pair loss, and in mice produces neonatal hydrocephalus [PMID:30383886, PMID:32709945, PMID:38091523]. Loss-of-function mutations in RSPH9 cause primary ciliary dyskinesia with central-pair abnormalities and male infertility due to sperm dysmotility [PMID:19200523, PMID:36873931].\",\n  \"teleology\": [\n    {\n      \"year\": 2009,\n      \"claim\": \"Establishing RSPH9 as a radial spoke head gene whose mutations cause primary ciliary dyskinesia answered the fundamental question of whether radial spoke head defects in humans produce a PCD phenotype with central pair abnormalities.\",\n      \"evidence\": \"Positional cloning in consanguineous families, zebrafish knockdown/rescue, and Chlamydomonas knockdown\",\n      \"pmids\": [\"19200523\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Precise position of RSPH9 within the spoke head architecture unknown\", \"Assembly hierarchy relative to other spoke head proteins not defined\", \"Mechanism linking spoke head loss to central pair destabilization unresolved\"]\n    },\n    {\n      \"year\": 2014,\n      \"claim\": \"Demonstrating that RSPH1 mutations cause co-loss of RSPH4A and RSPH9 established that the spoke head proteins are interdependent and that spoke head integrity is required for central pair stability.\",\n      \"evidence\": \"Targeted NGS, TEM, and high-resolution immunofluorescence of patient respiratory cilia\",\n      \"pmids\": [\"24518672\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direction of dependency (which protein recruits which) not resolved by co-loss data alone\", \"Whether RSPH9 loss is a cause or consequence of spoke head disassembly unclear\"]\n    },\n    {\n      \"year\": 2015,\n      \"claim\": \"Systematic immunofluorescence across RSPH9, RSPH4A, and RSPH1 patient genotypes resolved the assembly hierarchy, placing RSPH9 as the most downstream component that depends on both RSPH4A and RSPH1 for axonemal incorporation.\",\n      \"evidence\": \"Reciprocal high-resolution immunofluorescence across 16 families with defined biallelic mutations\",\n      \"pmids\": [\"25789548\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Direct protein-protein interactions mediating this hierarchy not demonstrated biochemically\", \"Whether RSPH9 has any autonomous structural role outside the spoke head unknown\"]\n    },\n    {\n      \"year\": 2016,\n      \"claim\": \"Demonstrating that RSPH9 localizes to both 9+2 and 9+0 axonemes and is required for structural integrity of both expanded RSPH9's role beyond canonical motile cilia to include non-canonical 9+0 cilia and kinocilia.\",\n      \"evidence\": \"CRISPR mutagenesis in zebrafish with fluorescence microscopy and acoustic startle behavioral assays\",\n      \"pmids\": [\"27687975\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Structural role of RSPH9 in 9+0 cilia that lack a canonical central pair unexplained\", \"Mechanism of hearing impairment in rsph9 mutants not fully elucidated\"]\n    },\n    {\n      \"year\": 2017,\n      \"claim\": \"Quantitative proteomics established RSPH9 as one of the most abundant non-tubulin proteins in human airway cilia axonemes, confirming it is a major structural constituent rather than a regulatory factor.\",\n      \"evidence\": \"Label-free LC/MSE absolute quantitative proteomics of human airway cilia\",\n      \"pmids\": [\"28282151\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Stoichiometry relative to other spoke head subunits not precisely determined\", \"Whether abundance varies across tissue-specific cilia not addressed\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"RNAi depletion of Rsph9 in mammalian ependymal cilia directly demonstrated that RSPH9 is required for central pair maintenance and planar beat pattern, converting beat motion from planar to rotational upon loss.\",\n      \"evidence\": \"RNAi knockdown in mouse ependymal cilia with high-speed video microscopy, TEM, and immunofluorescence\",\n      \"pmids\": [\"30383886\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Molecular mechanism by which spoke head loss destabilizes the central pair not resolved\", \"Whether rotational beat is the default state in absence of radial spoke constraint untested\"]\n    },\n    {\n      \"year\": 2018,\n      \"claim\": \"Finding that RSPH9 disappears from sperm flagella in Rsph6a knockout mice established that RSPH9 axonemal stability depends on RSPH6A, identifying an additional dependency in the sperm-specific spoke head.\",\n      \"evidence\": \"Rsph6a knockout mouse model with immunofluorescence of sperm flagella\",\n      \"pmids\": [\"30185526\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether RSPH6A directly binds RSPH9 or acts indirectly not determined\", \"Whether this dependency operates in respiratory cilia not tested\"]\n    },\n    {\n      \"year\": 2020,\n      \"claim\": \"Rsph9 knockout mice developed neonatal hydrocephalus with altered ependymal cilia beating, establishing the in vivo physiological consequence of complete RSPH9 loss in mammals.\",\n      \"evidence\": \"Rsph9 knockout mouse with high-speed video microscopy, TEM, and immunofluorescence\",\n      \"pmids\": [\"32709945\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Contribution of RSPH9 loss to situs defects not observed or addressed in this model\", \"Whether hydrocephalus arises purely from reduced CSF flow or has additional components unknown\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Demonstration that LRRC23 directly binds RSPH9 via its C-terminus and that LRRC23 loss ablates the RS3 head placed RSPH9 as a direct physical partner at the RS3 head structure, providing the first biochemically defined interaction for RSPH9.\",\n      \"evidence\": \"Recombinant protein pulldown with truncation mutants and cryo-electron tomography of LRRC23 mutant sperm\",\n      \"pmids\": [\"38091523\"],\n      \"confidence\": \"High\",\n      \"gaps\": [\"Full atomic-resolution structure of RSPH9 within the spoke head not available\", \"Whether RSPH9 bridges RS3 to additional spoke components not tested\"]\n    },\n    {\n      \"year\": 2023,\n      \"claim\": \"Identification of RSPH9 pathogenic variants causing isolated male infertility with sperm dysmotility extended the disease spectrum of RSPH9 deficiency beyond respiratory PCD.\",\n      \"evidence\": \"NGS, immunofluorescence on sperm flagella, high-speed video microscopy, TEM, semen analysis in affected individuals\",\n      \"pmids\": [\"36873931\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Genotype-phenotype correlation for specific RSPH9 variants incompletely characterized\", \"Whether partial RSPH9 loss can produce isolated infertility without respiratory phenotype needs larger cohorts\"]\n    },\n    {\n      \"year\": 2025,\n      \"claim\": \"Mass spectrometry and IQUB knockout analysis identified RSPH9 as a component of the RS1 head in sperm flagella, establishing that RSPH9 is shared across multiple radial spoke subtypes (RS1 and RS3).\",\n      \"evidence\": \"Protein mass spectrometry, western blotting, and Iqub knockout mouse model with TEM\",\n      \"pmids\": [\"39849482\"],\n      \"confidence\": \"Medium\",\n      \"gaps\": [\"Whether RSPH9 has identical or distinct roles in RS1 versus RS3 heads not resolved\", \"Stoichiometry of RSPH9 across RS subtypes unknown\"]\n    },\n    {\n      \"year\": null,\n      \"claim\": \"The atomic-resolution structure of RSPH9 within the radial spoke head, the mechanism by which spoke head integrity stabilizes the central pair apparatus, and the basis for tissue-specific differences in RSPH9 dependency (cilia vs. flagella) remain unresolved.\",\n      \"evidence\": \"\",\n      \"pmids\": [],\n      \"confidence\": \"High\",\n      \"gaps\": [\"No high-resolution structure of RSPH9 or its spoke head complex available\", \"Mechanism of central pair destabilization upon spoke head loss is unknown\", \"Tissue-specific regulatory differences between cilia and sperm flagella unexplained\"]\n    }\n  ],\n  \"mechanism_profile\": {\n    \"molecular_activity\": [\n      {\"term_id\": \"GO:0005198\", \"supporting_discovery_ids\": [0, 1, 3, 5, 12]}\n    ],\n    \"localization\": [\n      {\"term_id\": \"GO:0005929\", \"supporting_discovery_ids\": [0, 1, 2, 3, 5, 6, 12]},\n      {\"term_id\": \"GO:0005856\", \"supporting_discovery_ids\": [0, 3, 7, 10]}\n    ],\n    \"pathway\": [\n      {\"term_id\": \"R-HSA-1852241\", \"supporting_discovery_ids\": [0, 1, 3, 5, 7]}\n    ],\n    \"complexes\": [\n      \"Radial spoke head (RS1 head)\",\n      \"Radial spoke head (RS3 head)\"\n    ],\n    \"partners\": [\n      \"RSPH4A\",\n      \"RSPH1\",\n      \"RSPH6A\",\n      \"LRRC23\",\n      \"RSPH3\",\n      \"SPEF2\"\n    ],\n    \"other_free_text\": []\n  }\n}\n```"}