Mps1 phosphorylates Borealin to control Aurora B activity and chromosome alignment

Maintenance of chromosomal stability relies on coordination between various processes that are critical for proper chromosome segregation in mitosis. Here we show that monopolar spindle 1 (Mps1) kinase, which is essential for the mitotic checkpoint, also controls correction of improper chromosome attachments. We report that Borealin/DasraB, a member of the complex that regulates the Aurora B kinase, is directly phosphorylated by Mps1 on residues that are crucial for Aurora B activity and chromosome alignment. As a result, cells lacking Mps1 kinase activity fail to efficiently align chromosomes due to impaired Aurora B function at centromeres, leaving improper attachments uncorrected. Strikingly, Borealin/DasraB bearing phosphomimetic mutations restores Aurora B activity and alignment in Mps1-depleted cells. Mps1 thus coordinates attachment error correction and checkpoint signaling, two crucial responses to unproductive chromosome attachments.

 

Authors: 
N. Jelluma, A.B. Brenkman, N.J. van den Broek, C.W. Cruijsen, M.H. van Osch, S.M. Lens, R.H. Medema, G.J. Kops
Authors from the NMC: 
DOI: 
10.1016/j.cell.2007.11.046
Pages: 
2008; 132 (2): 233-246
Published in: 
Cell
Date of publication: 
January, 2008
Status of the publication: 
Published/accepted