Phosphorylation sites in BubR1 that regulate kinetochore attachment, tension, and mitotic exit.

ABSTRACT: BubR1 kinase is essential for the mitotic checkpoint and also for kinetochores to establish microtubule attachments. In this study, we report that BubR1 is phosphorylated in mitosis on four residues that differ from sites recently reported to be phosphorylated by Plk1 (Elowe, S., S. Hummer, A. Uldschmid, X. Li, and E.A. Nigg. 2007. Genes Dev. 21:2205-2219; Matsumura, S., F. Toyoshima, and E. Nishida. 2007. J. Biol. Chem. 282:15217-15227). S670, the most conserved residue, is phosphorylated at kinetochores at the onset of mitosis and dephosphorylated before anaphase onset. Unlike the Plk1-dependent S676 phosphorylation, S670 phosphorylation is sensitive to microtubule attachments but not to kinetochore tension. Functionally, phosphorylation of S670 is essential for error correction and for

SUBMITTER: Huang H 

PROVIDER: S-EPMC2582891 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature