title: Association of a 66 kDa homolog of Chlamydomonas DC2, a subunit of the outer arm docking complex, with outer arm dynein of sperm flagella in the ascidian Ciona intestinalis.
abstract: We previously identified a 66 kDa axonemal protein (Ci-Axp66.0) in sperm of the ascidian Ciona intestinalis. Here we found that Ci-Axp66.0 shows sequence similarity to the DC2 subunit of the Chlamydomonas outer arm docking complex. Analysis of secondary structure of Ci-Axp66.0 suggested that the N-terminal two-thirds of the molecule is rich in coiled coil structure, as in Chlamydomonas DC2. Immunogold localization revealed that it is located in the vicinity of outer arm dynein. Ci-Axp66.0 was partly extracted from the axonemes by a high salt solution and co-purified with outer arm dynein. This co-purification was not affected by the absence of Mg(2+) in isolation buffer, indicating that Ci-Axp66.0 is associated with outer arm dynein. These results suggest that Ci-Axp66.0 is a component of the outer arm dynein docking complex in the axonemes of Ciona sperm.
authors.affiliation: Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Sendai, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Ushimaru
authors.forename: Aru
authors.initials: A
authors.lastname: Konno
authors.forename: Maiko
authors.initials: M
authors.lastname: Kaizu
authors.forename: Kazuo
authors.initials: K
authors.lastname: Ogawa
authors.forename: Nori
authors.initials: N
authors.lastname: Satoh
authors.forename: Kazuo
authors.initials: K
authors.lastname: Inaba
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002696:Chlamydomonas / Q000378:metabolism; D002938:Ciona intestinalis / Q000737:chemistry*; D004398:Dyneins / Q000032:analysis*; D008297:Male; D008969:Molecular Sequence Data; D008970:Molecular Weight; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D013081:Sperm Motility; D013082:Sperm Tail / Q000737:chemistry*; D013094:Spermatozoa / Q000201:enzymology*
chemical_list: D015800:Protozoan Proteins; D004398:Dyneins