Proximity labeling of axonemal protein CFAP91 identifies EFCAB5 that regulates sperm motility.

ABSTRACT: Radial spokes (RSs) are conserved multimolecular structures attached to the axonemal microtubule doublets and are essential for the motility control of both cilia and sperm flagella. CFAP91, an RS3 protein, is implicated in human male infertility, yet its molecular function remains poorly understood. Here, we demonstrate that Cfap91 knockout (KO) mice exhibit impaired sperm flagellum formation and male infertility. Using a transgenic rescue model expressing FLAG- and BioID2-tagged CFAP91, we reveal that CFAP91 immunoprecipitates with RS3 proteins CFAP251 and LRRC23, whose localization is disrupted in Cfap91 KO sperm flagella. In addition, proximity labeling in mature spermatozoa identifies EFCAB5 as a sperm-specific CFAP91-proximal component. We show that Efcab5 KO males exhibit reduced sp

SUBMITTER: Wang H 

PROVIDER: S-EPMC12423330 | biostudies-literature | 2025 Sep

REPOSITORIES: biostudies-literature