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The cdc25 tyrosine phosphatase is known to activate cdc2 kinase in the G2/M transition by dephosphorylation of tyrosine 15. To determine how entry into M-phase in eukaryotic cells is controlled, we have investigated the regulation of the cdc25 protein in Xenopus eggs and oocytes. Two closely related Xenopus cdc25 genes have been cloned and sequenced and specific antibodies generated. The cdc25 phosphatase activity oscillates in both meiotic and mitotic cell cycles, being low in interphase and high in M-phase. Increased activity of cdc25 at M-phase is accompanied by increased phosphorylation that retards electrophoretic mobility in gels from 76 to 92 kDa. Treatment of cdc25 with either phosphatase 1 or phosphatase 2A removes phosphate from cdc25, reverses the mobility shift, and decreases its ability to activate cdc2 kinase. Furthermore, the addition of okadaic acid to egg extracts arrested in S-phase by aphidicolin causes phosphorylation and activation of the cdc25 protein before cyclin B/cdc2 kinase activation. These results demonstrate that the activity of the cdc25 phosphatase at the G2/M transition is directly regulated through changes in its phosphorylation state.
Amon,
Regulation of p34CDC28 tyrosine phosphorylation is not required for entry into mitosis in S. cerevisiae.
1992, Pubmed,
Xenbase
Amon,
Regulation of p34CDC28 tyrosine phosphorylation is not required for entry into mitosis in S. cerevisiae.
1992,
Pubmed
,
Xenbase
Axton,
One of the protein phosphatase 1 isoenzymes in Drosophila is essential for mitosis.
1990,
Pubmed
Booher,
Involvement of a type 1 protein phosphatase encoded by bws1+ in fission yeast mitotic control.
1989,
Pubmed
Cohen,
The structure and regulation of protein phosphatases.
1989,
Pubmed
Cyert,
Regulation of MPF activity in vitro.
1988,
Pubmed
,
Xenbase
Dasso,
Completion of DNA replication is monitored by a feedback system that controls the initiation of mitosis in vitro: studies in Xenopus.
1990,
Pubmed
,
Xenbase
Doonan,
The bimG gene of Aspergillus nidulans, required for completion of anaphase, encodes a homolog of mammalian phosphoprotein phosphatase 1.
1989,
Pubmed
Draetta,
Human cdc2 protein kinase is a major cell-cycle regulated tyrosine kinase substrate.
,
Pubmed
Dunphy,
The cdc25 protein contains an intrinsic phosphatase activity.
1991,
Pubmed
Dunphy,
Fission yeast p13 blocks mitotic activation and tyrosine dephosphorylation of the Xenopus cdc2 protein kinase.
1989,
Pubmed
,
Xenbase
Edgar,
Genetic control of cell division patterns in the Drosophila embryo.
1989,
Pubmed
Enoch,
Mutation of fission yeast cell cycle control genes abolishes dependence of mitosis on DNA replication.
1990,
Pubmed
Enoch,
Coupling M phase and S phase: controls maintaining the dependence of mitosis on chromosome replication.
1991,
Pubmed
Félix,
Cdc2 H1 kinase is negatively regulated by a type 2A phosphatase in the Xenopus early embryonic cell cycle: evidence from the effects of okadaic acid.
1990,
Pubmed
,
Xenbase
Galaktionov,
Specific activation of cdc25 tyrosine phosphatases by B-type cyclins: evidence for multiple roles of mitotic cyclins.
1991,
Pubmed
Gautier,
cdc25 is a specific tyrosine phosphatase that directly activates p34cdc2.
1991,
Pubmed
,
Xenbase
Gould,
Tyrosine phosphorylation of the fission yeast cdc2+ protein kinase regulates entry into mitosis.
1989,
Pubmed
Guan,
A Tyr/Ser protein phosphatase encoded by vaccinia virus.
1991,
Pubmed
Guan,
Protein tyrosine phosphatase activity of an essential virulence determinant in Yersinia.
1990,
Pubmed
Hartwell,
Checkpoints: controls that ensure the order of cell cycle events.
1989,
Pubmed
Izumi,
Insulin and platelet-derived growth factor stimulate phosphorylation of the c-raf product at serine and threonine residues in intact cells.
1991,
Pubmed
Izumi,
Phosphorylation of Xenopus cyclins B1 and B2 is not required for cell cycle transitions.
1991,
Pubmed
,
Xenbase
Jessus,
Oscillation of MPF is accompanied by periodic association between cdc25 and cdc2-cyclin B.
1992,
Pubmed
,
Xenbase
Kozak,
Point mutations define a sequence flanking the AUG initiator codon that modulates translation by eukaryotic ribosomes.
1986,
Pubmed
Krek,
Differential phosphorylation of vertebrate p34cdc2 kinase at the G1/S and G2/M transitions of the cell cycle: identification of major phosphorylation sites.
1991,
Pubmed
Kumagai,
The cdc25 protein controls tyrosine dephosphorylation of the cdc2 protein in a cell-free system.
1991,
Pubmed
,
Xenbase
Lee,
INH, a negative regulator of MPF, is a form of protein phosphatase 2A.
1991,
Pubmed
,
Xenbase
Lee,
cdc25+ encodes a protein phosphatase that dephosphorylates p34cdc2.
1992,
Pubmed
,
Xenbase
Lohka,
Induction of nuclear envelope breakdown, chromosome condensation, and spindle formation in cell-free extracts.
1985,
Pubmed
,
Xenbase
Maller,
Mitotic control.
1991,
Pubmed
Millar,
p80cdc25 mitotic inducer is the tyrosine phosphatase that activates p34cdc2 kinase in fission yeast.
1991,
Pubmed
Millar,
p55CDC25 is a nuclear protein required for the initiation of mitosis in human cells.
1991,
Pubmed
Moll,
The role of phosphorylation and the CDC28 protein kinase in cell cycle-regulated nuclear import of the S. cerevisiae transcription factor SWI5.
1991,
Pubmed
Moreno,
Regulation of mitosis by cyclic accumulation of p80cdc25 mitotic inducer in fission yeast.
1990,
Pubmed
Murray,
The role of cyclin synthesis and degradation in the control of maturation promoting factor activity.
1989,
Pubmed
,
Xenbase
Murray,
Cyclin synthesis drives the early embryonic cell cycle.
1989,
Pubmed
,
Xenbase
Nurse,
Universal control mechanism regulating onset of M-phase.
1990,
Pubmed
Ohkura,
The fission yeast dis2+ gene required for chromosome disjoining encodes one of two putative type 1 protein phosphatases.
1989,
Pubmed
Rebagliati,
Identification and cloning of localized maternal RNAs from Xenopus eggs.
1985,
Pubmed
,
Xenbase
Robbins,
Two interdependent basic domains in nucleoplasmin nuclear targeting sequence: identification of a class of bipartite nuclear targeting sequence.
1991,
Pubmed
,
Xenbase
Russell,
Conservation of mitotic controls in fission and budding yeasts.
1989,
Pubmed
Russell,
cdc25+ functions as an inducer in the mitotic control of fission yeast.
1986,
Pubmed
Sadhu,
Human homolog of fission yeast cdc25 mitotic inducer is predominantly expressed in G2.
1990,
Pubmed
Sorger,
S-phase feedback control in budding yeast independent of tyrosine phosphorylation of p34cdc28.
1992,
Pubmed
,
Xenbase
Strausfeld,
Dephosphorylation and activation of a p34cdc2/cyclin B complex in vitro by human CDC25 protein.
1991,
Pubmed
Streuli,
Distinct functional roles of the two intracellular phosphatase like domains of the receptor-linked protein tyrosine phosphatases LCA and LAR.
1990,
Pubmed
Studier,
Use of T7 RNA polymerase to direct expression of cloned genes.
1990,
Pubmed
Tung,
The catalytic subunits of protein phosphatase-1 and protein phosphatase 2A are distinct gene products.
1984,
Pubmed
Walker,
Multiple roles for protein phosphatase 1 in regulating the Xenopus early embryonic cell cycle.
1992,
Pubmed
,
Xenbase
Walker,
Role for cyclin A in the dependence of mitosis on completion of DNA replication.
1991,
Pubmed
,
Xenbase
