Differential light chain assembly influences outer arm dynein motor function
Authors
DiBella, Linda M.Gorbatyuk, Oksana
Sakato, Miho
Wakabayashi, Ken-ichi
Patel-King, Ramila S.
Pazour, Gregory J.
Witman, George B.
King, Stephen M.
Document Type
Journal ArticlePublication Date
2005-10-01Keywords
Amino Acid SequenceAnimals
Base Sequence
Binding Sites
Carrier Proteins
Chlamydomonas reinhardtii
Drosophila Proteins
Dynein ATPase
Ethyldimethylaminopropyl Carbodiimide
Humans
Mice
Molecular Sequence Data
Sequence Alignment
Sequence Homology, Amino Acid
Cell Biology
Metadata
Show full item recordAbstract
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.Source
Mol Biol Cell. 2005 Dec;16(12):5661-74. Epub 2005 Sep 29. Link to article on publisher's siteDOI
10.1091/mbc.E05-08-0732Permanent Link to this Item
http://hdl.handle.net/20.500.14038/26530PubMed ID
16195342Related Resources
Link to Article in PubMedae974a485f413a2113503eed53cd6c53
10.1091/mbc.E05-08-0732
Scopus Count
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