The chromosomal association of condensin II is regulated by a noncatalytic function of PP2A.
Mitotic chromosomal assembly in vertebrates is regulated by condensin I and condensin II, which work cooperatively but have different chromosomal localization profiles and make distinct mechanistic contributions to this process. We show here that protein phosphatase 2A (PP2A), which interacts with condensin II but not condensin I, plays an essential role in targeting condensin II to chromosomes. Unexpectedly, our data indicate that PP2A acts as a recruiter protein rather than a catalytic enzyme to target condensin II to chromosomes. This recruiting activity of PP2A was inhibited by okadaic acid, but not by fostriecin, even though both molecules strongly inhibited the catalytic activity of PP2A. Additionally, we found that the chromokinesin KIF4a is also targeted to chromosomes via the noncatalytic activity of PP2A. Thus, our studies reveal a previously unknown contribution of PP2A to chromosome assembly.
Takemoto
Ai
A
Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba Science City, Ibaraki, Japan.
Maeshima
Kazuhiro
K
Ikehara
Tsuyoshi
T
Yamaguchi
Kazumitsu
K
Murayama
Akiko
A
Imamura
Shihoko
S
Imamoto
Naoko
N
Yokoyama
Shigeyuki
S
Hirano
Tatsuya
T
Watanabe
Yoshinori
Y
Hanaoka
Fumio
F
Yanagisawa
Junn
J
Kimura
Keiji
K
D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000475:Alkenes / Q000494:pharmacology; D000818:Animals; D002460:Cell Line; D002478:Cells, Cultured; D002875:Chromosomes / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006801:Humans; D016547:Kinesins / Q000378:metabolism; D008954:Models, Biological; D046912:Multiprotein Complexes / Q000378:metabolism*; D019319:Okadaic Acid / Q000494:pharmacology; D011090:Polyenes; D054648:Protein Phosphatase 2 / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011753:Pyrones / Q000494:pharmacology; D014981:Xenopus
D000475:Alkenes; D004268:DNA-Binding Proteins; D004791:Enzyme Inhibitors; D046912:Multiprotein Complexes; D011090:Polyenes; D011753:Pyrones; C108312:condensin complexes; D019319:Okadaic Acid; D054648:Protein Phosphatase 2; D000251:Adenosine Triphosphatases; C484228:KIF4A protein, human; D016547:Kinesins; C040313:fostriecin