Aurora-B regulates the cleavage furrow-specific vimentin phosphorylation in the cytokinetic process.
Aurora-B is an evolutionally conserved protein kinase that regulates several mitotic events including cytokinesis. We previously demonstrated the possible existence of a protein kinase that phosphorylates at least Ser-72 on vimentin, the most widely expressed intermediate filament protein, in the cleavage furrow-specific manner. Here we showed that vimentin-Ser-72 phosphorylation occurred specifically at the border of the Aurora-B-localized area from anaphase to telophase. Expression of a dominant-negative mutant of Aurora-B led to a reduction of this vimentin-Ser-72 phosphorylation. In vitro analyses revealed that Aurora-B phosphorylates vimentin at approximately 2 mol phosphate/mol of substrate for 30 min and that this phosphorylation dramatically inhibits vimentin filament formation. We further identified eight Aurora-B phosphorylation sites, including Ser-72 on vimentin, and then constructed the mutant vimentin in which these identified sites are changed into Ala. Cells expressing this mutant formed an unusually long bridge-like intermediate filament structure between unseparated daughter cells. We then identified important phosphorylation sites for the bridge phenotype. Our findings indicate that Aurora-B regulates the cleavage furrow-specific vimentin phosphorylation and controls vimentin filament segregation in cytokinetic process.
Goto
Hidemasa
H
Division of Biochemistry, Aichi Cancer Center Research Institute, Chikusa-ku, Nagoya, Japan.
Yasui
Yoshihiro
Y
Kawajiri
Aie
A
Nigg
Erich A
EA
Terada
Yasuhiko
Y
Tatsuka
Masaaki
M
Nagata
Koh-ichi
K
Inagaki
Masaki
M
D000595:Amino Acid Sequence; D000818:Animals; D064107:Aurora Kinase B; D064127:Aurora Kinases; D002453:Cell Cycle; D051379:Mice; D008969:Molecular Sequence Data; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D014746:Vimentin / Q000737:chemistry / Q000378:metabolism*
D011994:Recombinant Proteins; D014746:Vimentin; C576924:Aurkb protein, mouse; D064107:Aurora Kinase B; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases