Functional significance of the specific sites phosphorylated in desmin at cleavage furrow: Aurora-B may phosphorylate and regulate type III intermediate filaments during cytokinesis coordinatedly with Rho-kinase.
Aurora-B is a protein kinase required for chromosome segregation and the progression of cytokinesis during the cell cycle. We report here that Aurora-B phosphorylates GFAP and desmin in vitro, and this phosphorylation leads to a reduction in filament forming ability. The sites phosphorylated by Aurora-B; Thr-7/Ser-13/Ser-38 of GFAP, and Thr-16 of desmin are common with those related to Rho-associated kinase (Rho-kinase), which has been reported to phosphorylate GFAP and desmin at cleavage furrow during cytokinesis. We identified Ser-59 of desmin to be a specific site phosphorylated by Aurora-B in vitro. Use of an antibody that specifically recognized desmin phosphorylated at Ser-59 led to the finding that the site is also phosphorylated specifically at the cleavage furrow during cytokinesis in Saos-2 cells. Desmin mutants, in which in vitro phosphorylation sites by Aurora-B and/or Rho-kinase are changed to Ala or Gly, cause dramatic defects in filament separation between daughter cells in cytokinesis. The results presented here suggest the possibility that Aurora-B may regulate cleavage furrow-specific phosphorylation and segregation of type III IFs coordinatedly with Rho-kinase during cytokinesis.
Kawajiri
Aie
A
Division of Biochemistry, Aichi Cancer Center Research Institute, Chikusa-ku, Nagoya 464-8681, Japan.
Yasui
Yoshihiro
Y
Goto
Hidemasa
H
Tatsuka
Masaaki
M
Takahashi
Masahide
M
Nagata
Koh-Ichi
K
Inagaki
Masaki
M
D000595:Amino Acid Sequence; D000818:Animals; D064107:Aurora Kinase B; D064127:Aurora Kinases; D001665:Binding Sites / Q000235:genetics; D019556:COS Cells; D002455:Cell Division; D002460:Cell Line; D003893:Desmin / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D005904:Glial Fibrillary Acidic Protein / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D007382:Intermediate Filaments / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012694:Serine / Q000737:chemistry; D054460:rho-Associated Kinases
D003893:Desmin; D005904:Glial Fibrillary Acidic Protein; D047908:Intracellular Signaling Peptides and Proteins; D011993:Recombinant Fusion Proteins; D012694:Serine; C576921:AURKB protein, human; D064107:Aurora Kinase B; D064127:Aurora Kinases; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases