title: Proteomic characterization of sperm radial spokes identifies a novel spoke protein with an ubiquitin domain.
abstract: Radial spokes are T-shaped protein complexes important for the regulation of axonemal dyneins in eukaryotic cilia and flagella. Using a functional proteomics approach, we identified six spoke proteins in sperm flagella of the ascidian Ciona intestinalis. Many of the domain/motif structures in spoke proteins are commonly found in flagella of both Ciona sperm and Chlamydomonas, but interestingly they often distribute over non-orthologous protein components. A novel 116 kDa protein named CMUB116 has both an ubiquitin domain and an IQ motif. It has orthologs in vertebrates, but not in Chlamydomonas. Furthermore, the results obtained by immunological analysis provide strong indication that CMUB116 is located at the stalk of radial spokes, where it is associated with MORN40.
authors.affiliation: Shimoda Marine Research Center, University of Tsukuba, Shimoda, Shizuoka, Japan.
authors.forename: Yuhkoh
authors.initials: Y
authors.lastname: Satouh
authors.forename: Kazuo
authors.initials: K
authors.lastname: Inaba
mesh_terms: D000818:Animals; D054468:Axoneme / Q000737:chemistry; D002352:Carrier Proteins / Q000737:chemistry*; D002938:Ciona intestinalis / Q000378:metabolism; D018076:DNA, Complementary; D007150:Immunohistochemistry; D008297:Male; D008957:Models, Genetic; D010449:Peptide Mapping; D040901:Proteomics; D015800:Protozoan Proteins / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013082:Sperm Tail / Q000737:chemistry*; D025801:Ubiquitin / Q000737:chemistry* / Q000378:metabolism
chemical_list: D002352:Carrier Proteins; D018076:DNA, Complementary; D015800:Protozoan Proteins; D025801:Ubiquitin