IC97 is a novel intermediate chain of I1 dynein that interacts with tubulin and regulates interdoublet sliding
UMass Chan Affiliations
Department of Cell BiologyDocument Type
Journal ArticlePublication Date
2009-07-08Keywords
Algal ProteinsAmino Acid Sequence
Animals
Axoneme
Base Sequence
Blotting, Western
Chlamydomonas reinhardtii
Cloning, Molecular
Dyneins
ImmunoprecipitationMicrotubulesMolecular Sequence DataMutationProtein BindingProtein SubunitsSequence Analysis, DNASequence Homology, Amino AcidTubulinCell Biology
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Our goal is to understand the assembly and regulation of flagellar dyneins, particularly the Chlamydomonas inner arm dynein called I1 dynein. Here, we focus on the uncharacterized I1-dynein IC IC97. The IC97 gene encodes a novel IC without notable structural domains. IC97 shares homology with the murine lung adenoma susceptibility 1 (Las1) protein--a candidate tumor suppressor gene implicated in lung tumorigenesis. Multiple, independent biochemical assays determined that IC97 interacts with both alpha- and beta-tubulin subunits within the axoneme. I1-dynein assembly mutants suggest that IC97 interacts with both the IC138 and IC140 subunits within the I1-dynein motor complex and that IC97 is part of a regulatory complex that contains IC138. Microtubule sliding assays, using axonemes containing I1 dynein but devoid of IC97, show reduced microtubule sliding velocities that are not rescued by kinase inhibitors, revealing a critical role for IC97 in I1-dynein function and control of dynein-driven motility.Source
Mol Biol Cell. 2009 Jul;20(13):3044-54. Epub 2009 May 6. Link to article on publisher's siteDOI
10.1091/mbc.E09-04-0276Permanent Link to this Item
http://hdl.handle.net/20.500.14038/51089Related Resources
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