title: Novel 44-kilodalton subunit of axonemal Dynein conserved from chlamydomonas to mammals.
abstract: Cilia and flagella have multiple dyneins in their inner and outer arms. Chlamydomonas inner-arm dynein contains at least seven major subspecies (dynein a to dynein g), of which all but dynein f (also called dynein I1) are the single-headed type that are composed of a single heavy chain, actin, and either centrin or a 28-kDa protein (p28). Dynein d was found to associate with two additional proteins of 38 kDa (p38) and 44 kDa (p44). Following the characterization of the p38 protein (R. Yamamoto, H. A. Yanagisawa, T. Yagi, and R. Kamiya, FEBS Lett. 580:6357-6360, 2006), we have identified p44 as a novel component of dynein d by using an immunoprecipitation approach. p44 is present along the length of the axonemes and is diminished, but not absent, in the ida4 and ida5 mutants, both lacking this dynein. In the ida5 axoneme, p44 and p38 appear to form a complex, suggesting that they constitute the docking site of dynein d on the outer doublet. p44 has potential homologues in other ciliated organisms. For example, the mouse homologue of p44, NYD-SP14, was found to be strongly expressed in tissues with motile cilia and flagella. These results suggest that inner-arm dynein d and its subunit organization are widely conserved.
authors.affiliation: Department of Biological Sciences, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Ryosuke
authors.initials: R
authors.lastname: Yamamoto
authors.forename: Haru-Aki
authors.initials: HA
authors.lastname: Yanagisawa
authors.forename: Toshiki
authors.initials: T
authors.lastname: Yagi
authors.forename: Ritsu
authors.initials: R
authors.lastname: Kamiya
mesh_terms: D020418:Algal Proteins / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D054468:Axoneme / Q000201:enzymology*; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D002465:Cell Movement; D016825:Chlamydomonas reinhardtii / Q000201:enzymology* / Q000235:genetics; D002923:Cilia / Q000378:metabolism; D017124:Conserved Sequence; D004398:Dyneins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D005407:Flagella / Q000235:genetics / Q000378:metabolism; D005455:Fluorescent Antibody Technique; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism; D015151:Immunoblotting; D051379:Mice; D008969:Molecular Sequence Data; D021122:Protein Subunits; D015800:Protozoan Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011817:Rabbits; D017386:Sequence Homology, Amino Acid
chemical_list: D020418:Algal Proteins; D018398:Homeodomain Proteins; D021122:Protein Subunits; D015800:Protozoan Proteins; D004398:Dyneins