Protein kinases required for segregation of vimentin filaments in mitotic process.
Vimentin, one of type III intermediate filament (IF) proteins, is expressed not only in mesenchymal cells but also in most types of tumor cells. In the present study, we introduced several types of vimentin mutated at putative phosphorylation sites in its amino-terminal head domain into type III IF-negative T24 cells. Site-specific mutation induced the formation of an unusually long bridge-like IF structure between the unseparated daughter cells, although these mutants formed the filament network similar to wild type in interphase cells. Together with sites phosphorylated by Rho-kinase and protein kinase C (PKC), vimentin-Ser72, which can not be phosphorylated by any known vimentin kinase, was one of the mutation sites essential for this phenotype. We further demonstrated that vimentin-Ser72 was phosphorylated specifically at the cleavage furrow during cytokinesis. These observations suggest the existence of a novel protein kinase responsible for vimentin filament separation through the cleavage furrow-specific vimentin phosphorylation. We propose that Rho-kinase, PKC, and an unidentified vimentin-Ser72 kinase may play important roles in vimentin filament separation during cytokinesis.
Yasui
Y
Y
Division of Biochemistry, Aichi Cancer Center Research Institute, Chikusa-ku, Nagoya 464-8681, Japan.
Goto
H
H
Matsui
S
S
Manser
E
E
Lim
L
L
Nagata Ki
Inagaki
M
M
D008841:Actin Cytoskeleton / Q000378:metabolism*; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000235:genetics / Q000378:metabolism; D005904:Glial Fibrillary Acidic Protein / Q000235:genetics / Q000378:metabolism; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008938:Mitosis; D009154:Mutation; D010766:Phosphorylation; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism; D011494:Protein Kinases / Q000235:genetics / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism; D012694:Serine / Q000378:metabolism; D014162:Transfection; D014407:Tumor Cells, Cultured; D014746:Vimentin / Q000235:genetics* / Q000378:metabolism*; D054460:rho-Associated Kinases
D005904:Glial Fibrillary Acidic Protein; D047908:Intracellular Signaling Peptides and Proteins; D014746:Vimentin; D012694:Serine; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases; D054460:rho-Associated Kinases; D011493:Protein Kinase C; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases