title: Katanin regulates dynamics of microtubules and biogenesis of motile cilia.
abstract: The in vivo significance of microtubule severing and the mechanisms governing its spatial regulation are not well understood. In Tetrahymena, a cell type with elaborate microtubule arrays, we engineered null mutations in subunits of the microtubule-severing complex, katanin. We show that katanin activity is essential. The net effect of katanin on the polymer mass depends on the microtubule type and location. Although katanin reduces the polymer mass and destabilizes the internal network of microtubules, its activity increases the mass of ciliary microtubules. We also show that katanin reduces the levels of several types of post-translational modifications on tubulin of internal and cortical microtubules. Furthermore, katanin deficiencies phenocopy a mutation of beta-tubulin that prevents deposition of polymodifications (glutamylation and glycylation) on microtubules. We propose that katanin preferentially severs older, post-translationally modified segments of microtubules.
authors.affiliation: Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA.
authors.forename: Neeraj
authors.initials: N
authors.lastname: Sharma
authors.forename: Jessica
authors.initials: J
authors.lastname: Bryant
authors.forename: Dorota
authors.initials: D
authors.lastname: Wloga
authors.forename: Rachel
authors.initials: R
authors.lastname: Donaldson
authors.forename: Richard C
authors.initials: RC
authors.lastname: Davis
authors.forename: Maria
authors.initials: M
authors.lastname: Jerka-Dziadosz
authors.forename: Jacek
authors.initials: J
authors.lastname: Gaertig
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics / Q000502:physiology*; D000818:Animals; D002923:Cilia / Q000502:physiology / Q000648:ultrastructure; D000074201:Katanin; D008870:Microtubules / Q000502:physiology*; D009154:Mutation; D010802:Phylogeny; D011499:Protein Processing, Post-Translational; D015800:Protozoan Proteins / Q000235:genetics / Q000502:physiology*; D016808:Tetrahymena thermophila / Q000502:physiology* / Q000648:ultrastructure; D014404:Tubulin / Q000378:metabolism
chemical_list: D015800:Protozoan Proteins; D014404:Tubulin; D000251:Adenosine Triphosphatases; D000074201:Katanin