Phosphorylation and activation of 13S condensin by Cdc2 in vitro.
13S condensin is a multisubunit protein complex essential for mitotic chromosome condensation in Xenopus egg extracts. Purified 13S condensin introduces positive supercoils into DNA in the presence of topoisomerase I and adenosine triphosphate in vitro. The supercoiling activity of 13Scondensin was regulated by mitosis-specific phosphorylation. Immunodepletion, in vitro phosphorylation, and peptide-mapping experiments indicated that Cdc2 is likely to be the kinase that phosphorylates and activates 13S condensin. Multiple Cdc2 phosphorylation sites are clustered in the carboxyl-terminal domain of the XCAP-D2 (Xenopus chromosome-associated polypeptide D2) subunit. These results suggest that phosphorylation of 13Scondensin by Cdc2 may trigger mitotic chromosome condensation in vitro.
Kimura
K
K
Cold Spring Harbor Laboratory, Post Office Box 100, 1 Bungtown Road, Cold Spring Harbor, NY 11724, USA.
Hirano
M
M
Kobayashi
R
R
Hirano
T
T
D000251:Adenosine Triphosphatases / Q000737:chemistry / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D016203:CDC2 Protein Kinase / Q000378:metabolism*; D002875:Chromosomes / Q000737:chemistry / Q000378:metabolism*; D004270:DNA, Circular / Q000737:chemistry / Q000378:metabolism; D004278:DNA, Superhelical / Q000737:chemistry*; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism*; D004789:Enzyme Activation; D007399:Interphase; D008938:Mitosis; D008969:Molecular Sequence Data; D046912:Multiprotein Complexes; D009690:Nucleic Acid Conformation; D010449:Peptide Mapping; D010766:Phosphorylation; D014981:Xenopus
D004270:DNA, Circular; D004278:DNA, Superhelical; D004268:DNA-Binding Proteins; D046912:Multiprotein Complexes; C108312:condensin complexes; D016203:CDC2 Protein Kinase; D000251:Adenosine Triphosphatases