Witman Lab Publications

UMMS Affiliation

Department of Cell Biology

Publication Date


Document Type



Algal Proteins; Amino Acid Sequence; Animals; Axoneme; Base Sequence; Blotting, Western; Chlamydomonas reinhardtii; Cloning, Molecular; Dyneins; Immunoprecipitation; Microtubules; Molecular Sequence Data; Mutation; Protein Binding; Protein Subunits; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Tubulin


Cell Biology


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.

DOI of Published Version



Mol Biol Cell. 2009 Jul;20(13):3044-54. Epub 2009 May 6. Link to article on publisher's site

Journal/Book/Conference Title

Molecular biology of the cell

Related Resources

Link to Article in PubMed

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