Chlamydomonas IFT70/CrDYF-1 is a core component of IFT particle complex B and is required for flagellar assembly.
DYF-1 is a highly conserved protein essential for ciliogenesis in several model organisms. In Caenorhabditis elegans, DYF-1 serves as an essential activator for an anterograde motor OSM-3 of intraflagellar transport (IFT), the ciliogenesis-required motility that mediates the transport of flagellar precursors and removal of turnover products. In zebrafish and Tetrahymena DYF-1 influences the cilia tubulin posttranslational modification and may have more ubiquitous function in ciliogenesis than OSM-3. Here we address how DYF-1 biochemically interacts with the IFT machinery by using the model organism Chlamydomonas reinhardtii, in which the anterograde IFT does not depend on OSM-3. Our results show that this protein is a stoichiometric component of the IFT particle complex B and interacts directly with complex B subunit IFT46. In concurrence with the established IFT protein nomenclature, DYF-1 is also named IFT70 after the apparent size of the protein. IFT70/CrDYF-1 is essential for the function of IFT in building the flagellum because the flagella of IFT70/CrDYF-1-depleted cells were greatly shortened. Together, these results demonstrate that IFT70/CrDYF-1 is a canonical subunit of IFT particle complex B and strongly support the hypothesis that the IFT machinery has species- and tissue-specific variations with functional ramifications.
Department of Biology, Texas A&M University, College Station, TX 77843-3258, USA.
Zhen-Chuan
ZC
Fan
Robert H
RH
Behal
Stefan
S
Geimer
Zhaohui
Z
Wang
Shana M
SM
Williamson
Haili
H
Zhang
Douglas G
DG
Cole
Hongmin
H
Qin
D020418:Algal Proteins / Q000737:chemistry / Q000378:metabolism*; D000595:Amino Acid Sequence; D054468:Axoneme / Q000378:metabolism / Q000648:ultrastructure; D002696:Chlamydomonas / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D017124:Conserved Sequence / Q000235:genetics; D005407:Flagella / Q000378:metabolism* / Q000648:ultrastructure; D055785:Gene Knockdown Techniques; D016547:Kinesins / Q000378:metabolism; D008969:Molecular Sequence Data; D011485:Protein Binding; D021122:Protein Subunits / Q000378:metabolism; D011994:Recombinant Proteins / Q000378:metabolism
D020418:Algal Proteins; D021122:Protein Subunits; D011994:Recombinant Proteins; D016547:Kinesins