title: Furry promotes acetylation of microtubules in the mitotic spindle by inhibition of SIRT2 tubulin deacetylase.
abstract: The structure and function of microtubules (MTs) are regulated by post-translational modifications of tubulin subunits, such as acetylation of the Lys40 residue of α-tubulin. Regulation of the organization and dynamics of MTs is essential for the precise formation of the mitotic spindle. Spindle MTs are highly acetylated, but the mechanism regulating this acetylation is largely unknown. Furry (Fry) is an evolutionarily conserved protein that binds to MTs and colocalizes with acetylated MTs in the mitotic spindle. In this study, we examined the role of Fry in the acetylation of MTs in the mitotic spindle. Depletion of Fry significantly reduced the level of MT acetylation in the mitotic spindle. Expression of the N-terminal fragment of Fry induced hyperacetylation of MTs in both mitotic and interphase cells. These results indicate that Fry promotes MT acetylation in the mitotic spindle. We also found that Fry binds to the tubulin deacetylase SIRT2, preferentially in mitotic cells. Cell-free experiments revealed that the N-terminal region of Fry is the domain responsible for binding to and inhibiting the tubulin-deacetylase activity of SIRT2. AGK2, a specific inhibitor of SIRT2, increased the level of MT acetylation in the mitotic spindle, indicating that SIRT2 is involved in the deacetylation of spindle MTs. Furthermore, AGK2 reversed the decrease in MT acetylation induced by Fry depletion. In summary, these results suggest that Fry plays a crucial role in promoting the level of MT acetylation in the mitotic spindle by inhibiting the tubulin-deacetylase activity of SIRT2.
authors.affiliation: Department of Biomolecular Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan.
authors.forename: Tomoaki
authors.initials: T
authors.lastname: Nagai
authors.forename: Masanori
authors.initials: M
authors.lastname: Ikeda
authors.forename: Shuhei
authors.initials: S
authors.lastname: Chiba
authors.forename: Shin-Ichiro
authors.initials: S
authors.lastname: Kanno
authors.forename: Kensaku
authors.initials: K
authors.lastname: Mizuno
mesh_terms: D000107:Acetylation / Q000187:drug effects; D000818:Animals; D018797:Cell Cycle Proteins; D055785:Gene Knockdown Techniques; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D008869:Microtubule-Associated Proteins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D008870:Microtubules / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D017239:Paclitaxel / Q000494:pharmacology; D011743:Pyrimidines / Q000494:pharmacology; D056565:Sirtuin 2 / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism*; D008941:Spindle Apparatus / Q000187:drug effects / Q000378:metabolism*; D013871:Thiones / Q000494:pharmacology; D014162:Transfection
chemical_list: D018797:Cell Cycle Proteins; C000655011:FRY protein, human; D008869:Microtubule-Associated Proteins; D011743:Pyrimidines; D013871:Thiones; C400223:monastrol; C474199:SIRT2 protein, human; D056565:Sirtuin 2; D017239:Paclitaxel
keywords: Furry; Microtubule; Mitotic spindle; SIRT2; Tubulin acetylation