Dephosphorylation of human p34cdc2 kinase on both Thr-14 and Tyr-15 by human cdc25B phosphatase.
In mammalian cells, p34cdc2 kinase undergoes phosphorylation at threonine-14, tyrosine-15 and threonine-161 in the S and G2 phases of the cell cycle. At the onset of mitosis, the kinase becomes dephosphorylated at threonine-14 and tyrosine-15, resulting in activation. Cdc25 phosphatase has been shown to dephosphorylate tyrosine-15 in vitro, but whether it also does at threonine-14 remains unclear. In this study, we have found that human cdc25B phosphatase dephosphorylates both threonine-14 and tyrosine-15 but not threonine-161.
Honda
R
R
Division of Biology, Faculty of Pharmaceutical Sciences, Kanazawa University, Ishikawa, Japan.
Ohba
Y
Y
Nagata
A
A
Okayama
H
H
Yasuda
H
H
D016203:CDC2 Protein Kinase / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism; D006367:HeLa Cells / Q000378:metabolism; D006801:Humans; D008938:Mitosis; D010449:Peptide Mapping; D010766:Phosphorylation; D011506:Proteins / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D013379:Substrate Specificity; D013912:Threonine / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism*; D020687:cdc25 Phosphatases
D011506:Proteins; D011994:Recombinant Proteins; D013912:Threonine; D014443:Tyrosine; D016203:CDC2 Protein Kinase; D020687:cdc25 Phosphatases