title: Kinesin-13 regulates the quantity and quality of tubulin inside cilia.
abstract: Kinesin-13, an end depolymerizer of cytoplasmic and spindle microtubules, also affects the length of cilia. However, in different models, depletion of kinesin-13 either lengthens or shortens cilia, and therefore the exact function of kinesin-13 in cilia remains unclear. We generated null mutations of all kinesin-13 paralogues in the ciliate Tetrahymena. One of the paralogues, Kin13Ap, localizes to the nuclei and is essential for nuclear divisions. The remaining two paralogues, Kin13Bp and Kin13Cp, localize to the cell body and inside assembling cilia. Loss of both Kin13Bp and Kin13Cp resulted in slow cell multiplication and motility, overgrowth of cell body microtubules, shortening of cilia, and synthetic lethality with either paclitaxel or a deletion of MEC-17/ATAT1, the α-tubulin acetyltransferase. The mutant cilia assembled slowly and contained abnormal tubulin, characterized by altered posttranslational modifications and hypersensitivity to paclitaxel. The mutant cilia beat slowly and axonemes showed reduced velocity of microtubule sliding. Thus kinesin-13 positively regulates the axoneme length, influences the properties of ciliary tubulin, and likely indirectly, through its effects on the axonemal microtubules, affects the ciliary dynein-dependent motility.
authors.affiliation: Department of Cellular Biology, University of Georgia, Athens, GA 30602;
authors.forename: Krishna Kumar
authors.initials: KK
authors.lastname: Vasudevan
authors.affiliation: Department of Cellular Biology, University of Georgia, Athens, GA 30602;
authors.forename: Yu-Yang
authors.initials: YY
authors.lastname: Jiang
authors.affiliation: Department of Cellular Biology, University of Georgia, Athens, GA 30602;
authors.forename: Karl F
authors.initials: KF
authors.lastname: Lechtreck
authors.affiliation: Department of Structural Biosciences, University of Tsukuba, Tsukuba, Ibaraki 305-8577, Japan;
authors.forename: Yasuharu
authors.initials: Y
authors.lastname: Kushida
authors.affiliation: Department of Cell Biology, Emory University, Atlanta, GA 30303;
authors.forename: Lea M
authors.initials: LM
authors.lastname: Alford
authors.affiliation: Department of Cell Biology, Emory University, Atlanta, GA 30303;
authors.forename: Winfield S
authors.initials: WS
authors.lastname: Sale
authors.affiliation: Department of Biological Sciences, State University of New York at Buffalo, Buffalo, NY 14260.
authors.forename: Todd
authors.initials: T
authors.lastname: Hennessey
authors.affiliation: Department of Cellular Biology, University of Georgia, Athens, GA 30602; jgaertig@uga.edu.
authors.forename: Jacek
authors.initials: J
authors.lastname: Gaertig
mesh_terms: D000123:Acetyltransferases / Q000235:genetics; D054468:Axoneme / Q000235:genetics / Q000502:physiology*; D002923:Cilia / Q000235:genetics / Q000502:physiology*; D055786:Gene Knockout Techniques; D016547:Kinesins / Q000235:genetics*; D009024:Morphogenesis / Q000187:drug effects / Q000235:genetics; D009154:Mutation; D017239:Paclitaxel / Q000494:pharmacology; D011499:Protein Processing, Post-Translational; D016808:Tetrahymena thermophila / Q000235:genetics / Q000502:physiology; D014404:Tubulin / Q000378:metabolism*
chemical_list: D014404:Tubulin; D000123:Acetyltransferases; C049182:alpha-tubulin acetylase; D016547:Kinesins; D017239:Paclitaxel