若林 憲一 所属 京都産業大学 生命科学部 産業生命科学科 職種 教授 |
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言語種別 | 英語 |
発行・発表の年月 | 2005/12 |
形態種別 | 研究論文 |
査読 | 査読あり |
標題 | Differential light chain assembly influences outer arm dynein motor function |
執筆形態 | その他 |
掲載誌名 | MOLECULAR BIOLOGY OF THE CELL |
出版社・発行元 | AMER SOC CELL BIOLOGY |
巻・号・頁 | 16(12),pp.5661-5674 |
著者・共著者 | LM DiBella,O Gorbatyuk,M Sakato,K Wakabayashi,RS Patel-King,GJ Pazour,GB Witman,SM King |
概要 | Tctex1 and Tctex2 were originally described as potential distorters/sterility factors in the non-Mendelian transmission of t-haplotypes in mice. These proteins have since been identified as subunits of cytoplasmic and/or axonemal dyneins. Within the Chlamydomonas flagellum, Tctex1 is a subunit of inner arm I1. We have now identified a second Tctex1-related protein (here termed LC9) in Chlamydomonas. LC9 copurifies with outer arm dynein in sucrose density gradients and is missing only in those strains completely lacking this motor. Zero-length cross-linking of purified outer arm dynein indicates that LC9 interacts directly with both the IC1 and IC2 intermediate chains. Immunoblot analysis revealed that LC2, LC6, and LC9 are missing in an IC2 mutant strain (oda6-r88) that can assemble outer arms but exhibits significantly reduced flagellar beat frequency. This defect is unlikely to be due to lack of LC6, because an LC6 null mutant (oda13) exhibits only a minor swimming abnormality. Using an LC2 null mutant (oda12-1), we find that although some outer arm dynein components assemble in the absence of LC2, they are nonfunctional. In contrast, dyneins from oda6-r88, which also lack LC2, retain some activity. Furthermore, we observed a synthetic assembly defect in an oda6-r88 oda12-1 double mutant. These data suggest that LC2, LC6, and LC9 have different roles in outer arm assembly and are required for wild-type motor function in the Chlamydomonas flagellum. |
DOI | 10.1091/mcb.E05-08-0732 |
ISSN | 1059-1524 |
PMID | 16195342 |