title: Katanin knockdown supports a role for microtubule severing in release of basal bodies before mitosis in Chlamydomonas.
abstract: Katanin is a microtubule-severing protein that participates in the regulation of cell cycle progression and in ciliary disassembly, but its precise role is not known for either activity. Our data suggest that in Chlamydomonas, katanin severs doublet microtubules at the proximal end of the flagellar transition zone, allowing disengagement of the basal body from the flagellum before mitosis. Using an RNA interference approach we have discovered that severe knockdown of the p60 subunit of katanin, KAT1, is achieved only in cells that also carry secondary mutations that disrupt ciliogenesis. Importantly, we observed that cells in the process of cell cycle-induced flagellar resorption sever the flagella from the basal bodies before resorption is complete, and we find that this process is defective in KAT1 knockdown cells.
authors.affiliation: Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada.
authors.forename: M Qasim
authors.initials: MQ
authors.lastname: Rasi
authors.forename: Jeremy D K
authors.initials: JD
authors.lastname: Parker
authors.forename: Jessica L
authors.initials: JL
authors.lastname: Feldman
authors.forename: Wallace F
authors.initials: WF
authors.lastname: Marshall
authors.forename: Lynne M
authors.initials: LM
authors.lastname: Quarmby
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D016825:Chlamydomonas reinhardtii / Q000166:cytology / Q000378:metabolism; D002923:Cilia / Q000378:metabolism* / Q000648:ultrastructure; D055785:Gene Knockdown Techniques; D000074201:Katanin; D008870:Microtubules / Q000378:metabolism* / Q000648:ultrastructure; D008938:Mitosis / Q000502:physiology*; D015800:Protozoan Proteins / Q000235:genetics / Q000378:metabolism*; D034622:RNA Interference
chemical_list: D015800:Protozoan Proteins; D000251:Adenosine Triphosphatases; D000074201:Katanin