IC97 is a novel intermediate chain of I1 dynein that interacts with tubulin and regulates interdoublet sliding.
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.
Wirschell
Maureen
M
Department of Cell Biology, Emory University School of Medicine, Atlanta, GA 30322, USA.
Yang
Chun
C
Yang
Pinfen
P
Fox
Laura
L
Yanagisawa
Haru-aki
HA
Kamiya
Ritsu
R
Witman
George B
GB
Porter
Mary E
ME
Sale
Winfield S
WS
D020418:Algal Proteins / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D054468:Axoneme / Q000378:metabolism / Q000502:physiology; D001483:Base Sequence; D015153:Blotting, Western; D016825:Chlamydomonas reinhardtii / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D003001:Cloning, Molecular; D004398:Dyneins / Q000235:genetics / Q000378:metabolism*; D047468:Immunoprecipitation; D008870:Microtubules / Q000378:metabolism / Q000502:physiology*; D008969:Molecular Sequence Data; D009154:Mutation; D011485:Protein Binding; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014404:Tubulin / Q000378:metabolism*
D020418:Algal Proteins; D021122:Protein Subunits; D014404:Tubulin; D004398:Dyneins