PMCCPMCCPMCC

Search tips
Search criteria 

Advanced

 
Logo of mbcLink to Publisher's site
 
Mol Biol Cell. 1992 August; 3(8): 927–939.
PMCID: PMC275649

Periodic changes in phosphorylation of the Xenopus cdc25 phosphatase regulate its activity.

Abstract

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.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (2.8M), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References.

Images in this article

Click on the image to see a larger version.

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Amon A, Surana U, Muroff I, Nasmyth K. Regulation of p34CDC28 tyrosine phosphorylation is not required for entry into mitosis in S. cerevisiae. Nature. 1992 Jan 23;355(6358):368–371. [PubMed]
  • Axton JM, Dombrádi V, Cohen PT, Glover DM. One of the protein phosphatase 1 isoenzymes in Drosophila is essential for mitosis. Cell. 1990 Oct 5;63(1):33–46. [PubMed]
  • Booher R, Beach D. Involvement of a type 1 protein phosphatase encoded by bws1+ in fission yeast mitotic control. Cell. 1989 Jun 16;57(6):1009–1016. [PubMed]
  • Cohen P. The structure and regulation of protein phosphatases. Annu Rev Biochem. 1989;58:453–508. [PubMed]
  • Cyert MS, Kirschner MW. Regulation of MPF activity in vitro. Cell. 1988 Apr 22;53(2):185–195. [PubMed]
  • Dasso M, Newport JW. Completion of DNA replication is monitored by a feedback system that controls the initiation of mitosis in vitro: studies in Xenopus. Cell. 1990 Jun 1;61(5):811–823. [PubMed]
  • Doonan JH, Morris NR. The bimG gene of Aspergillus nidulans, required for completion of anaphase, encodes a homolog of mammalian phosphoprotein phosphatase 1. Cell. 1989 Jun 16;57(6):987–996. [PubMed]
  • Draetta G, Piwnica-Worms H, Morrison D, Druker B, Roberts T, Beach D. Human cdc2 protein kinase is a major cell-cycle regulated tyrosine kinase substrate. Nature. 1988 Dec 22;336(6201):738–744. [PubMed]
  • Dunphy WG, Kumagai A. The cdc25 protein contains an intrinsic phosphatase activity. Cell. 1991 Oct 4;67(1):189–196. [PubMed]
  • Dunphy WG, Newport JW. Fission yeast p13 blocks mitotic activation and tyrosine dephosphorylation of the Xenopus cdc2 protein kinase. Cell. 1989 Jul 14;58(1):181–191. [PubMed]
  • Edgar BA, O'Farrell PH. Genetic control of cell division patterns in the Drosophila embryo. Cell. 1989 Apr 7;57(1):177–187. [PMC free article] [PubMed]
  • Enoch T, Nurse P. Mutation of fission yeast cell cycle control genes abolishes dependence of mitosis on DNA replication. Cell. 1990 Feb 23;60(4):665–673. [PubMed]
  • Enoch T, Nurse P. Coupling M phase and S phase: controls maintaining the dependence of mitosis on chromosome replication. Cell. 1991 Jun 14;65(6):921–923. [PubMed]
  • Félix MA, Cohen P, Karsenti E. 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. EMBO J. 1990 Mar;9(3):675–683. [PubMed]
  • Galaktionov K, Beach D. Specific activation of cdc25 tyrosine phosphatases by B-type cyclins: evidence for multiple roles of mitotic cyclins. Cell. 1991 Dec 20;67(6):1181–1194. [PubMed]
  • Gautier J, Solomon MJ, Booher RN, Bazan JF, Kirschner MW. cdc25 is a specific tyrosine phosphatase that directly activates p34cdc2. Cell. 1991 Oct 4;67(1):197–211. [PubMed]
  • Gould KL, Nurse P. Tyrosine phosphorylation of the fission yeast cdc2+ protein kinase regulates entry into mitosis. Nature. 1989 Nov 2;342(6245):39–45. [PubMed]
  • Guan KL, Broyles SS, Dixon JE. A Tyr/Ser protein phosphatase encoded by vaccinia virus. Nature. 1991 Mar 28;350(6316):359–362. [PubMed]
  • Guan KL, Dixon JE. Protein tyrosine phosphatase activity of an essential virulence determinant in Yersinia. Science. 1990 Aug 3;249(4968):553–556. [PubMed]
  • Hartwell LH, Weinert TA. Checkpoints: controls that ensure the order of cell cycle events. Science. 1989 Nov 3;246(4930):629–634. [PubMed]
  • Izumi T, Maller JL. Phosphorylation of Xenopus cyclins B1 and B2 is not required for cell cycle transitions. Mol Cell Biol. 1991 Aug;11(8):3860–3867. [PMC free article] [PubMed]
  • Izumi T, Tamemoto H, Nagao M, Kadowaki T, Takaku F, Kasuga M. Insulin and platelet-derived growth factor stimulate phosphorylation of the c-raf product at serine and threonine residues in intact cells. J Biol Chem. 1991 Apr 25;266(12):7933–7939. [PubMed]
  • Jessus C, Beach D. Oscillation of MPF is accompanied by periodic association between cdc25 and cdc2-cyclin B. Cell. 1992 Jan 24;68(2):323–332. [PubMed]
  • Kozak M. Point mutations define a sequence flanking the AUG initiator codon that modulates translation by eukaryotic ribosomes. Cell. 1986 Jan 31;44(2):283–292. [PubMed]
  • Krek W, Nigg EA. Differential phosphorylation of vertebrate p34cdc2 kinase at the G1/S and G2/M transitions of the cell cycle: identification of major phosphorylation sites. EMBO J. 1991 Feb;10(2):305–316. [PubMed]
  • Kumagai A, Dunphy WG. The cdc25 protein controls tyrosine dephosphorylation of the cdc2 protein in a cell-free system. Cell. 1991 Mar 8;64(5):903–914. [PubMed]
  • Lee MS, Ogg S, Xu M, Parker LL, Donoghue DJ, Maller JL, Piwnica-Worms H. cdc25+ encodes a protein phosphatase that dephosphorylates p34cdc2. Mol Biol Cell. 1992 Jan;3(1):73–84. [PMC free article] [PubMed]
  • Lee TH, Solomon MJ, Mumby MC, Kirschner MW. INH, a negative regulator of MPF, is a form of protein phosphatase 2A. Cell. 1991 Jan 25;64(2):415–423. [PubMed]
  • Lohka MJ, Maller JL. Induction of nuclear envelope breakdown, chromosome condensation, and spindle formation in cell-free extracts. J Cell Biol. 1985 Aug;101(2):518–523. [PMC free article] [PubMed]
  • Maller JL. Mitotic control. Curr Opin Cell Biol. 1991 Apr;3(2):269–275. [PubMed]
  • Millar JB, Blevitt J, Gerace L, Sadhu K, Featherstone C, Russell P. p55CDC25 is a nuclear protein required for the initiation of mitosis in human cells. Proc Natl Acad Sci U S A. 1991 Dec 1;88(23):10500–10504. [PubMed]
  • Millar JB, McGowan CH, Lenaers G, Jones R, Russell P. p80cdc25 mitotic inducer is the tyrosine phosphatase that activates p34cdc2 kinase in fission yeast. EMBO J. 1991 Dec;10(13):4301–4309. [PubMed]
  • Moll T, Tebb G, Surana U, Robitsch H, Nasmyth K. The role of phosphorylation and the CDC28 protein kinase in cell cycle-regulated nuclear import of the S. cerevisiae transcription factor SWI5. Cell. 1991 Aug 23;66(4):743–758. [PubMed]
  • Moreno S, Nurse P, Russell P. Regulation of mitosis by cyclic accumulation of p80cdc25 mitotic inducer in fission yeast. Nature. 1990 Apr 5;344(6266):549–552. [PubMed]
  • Murray AW, Kirschner MW. Cyclin synthesis drives the early embryonic cell cycle. Nature. 1989 May 25;339(6222):275–280. [PubMed]
  • Murray AW, Solomon MJ, Kirschner MW. The role of cyclin synthesis and degradation in the control of maturation promoting factor activity. Nature. 1989 May 25;339(6222):280–286. [PubMed]
  • Nurse P. Universal control mechanism regulating onset of M-phase. Nature. 1990 Apr 5;344(6266):503–508. [PubMed]
  • Ohkura H, Kinoshita N, Miyatani S, Toda T, Yanagida M. The fission yeast dis2+ gene required for chromosome disjoining encodes one of two putative type 1 protein phosphatases. Cell. 1989 Jun 16;57(6):997–1007. [PubMed]
  • Rebagliati MR, Weeks DL, Harvey RP, Melton DA. Identification and cloning of localized maternal RNAs from Xenopus eggs. Cell. 1985 Oct;42(3):769–777. [PubMed]
  • Robbins J, Dilworth SM, Laskey RA, Dingwall C. Two interdependent basic domains in nucleoplasmin nuclear targeting sequence: identification of a class of bipartite nuclear targeting sequence. Cell. 1991 Feb 8;64(3):615–623. [PubMed]
  • Russell P, Moreno S, Reed SI. Conservation of mitotic controls in fission and budding yeasts. Cell. 1989 Apr 21;57(2):295–303. [PubMed]
  • Russell P, Nurse P. cdc25+ functions as an inducer in the mitotic control of fission yeast. Cell. 1986 Apr 11;45(1):145–153. [PubMed]
  • Sadhu K, Reed SI, Richardson H, Russell P. Human homolog of fission yeast cdc25 mitotic inducer is predominantly expressed in G2. Proc Natl Acad Sci U S A. 1990 Jul;87(13):5139–5143. [PubMed]
  • Sorger PK, Murray AW. S-phase feedback control in budding yeast independent of tyrosine phosphorylation of p34cdc28. Nature. 1992 Jan 23;355(6358):365–368. [PubMed]
  • Strausfeld U, Labbé JC, Fesquet D, Cavadore JC, Picard A, Sadhu K, Russell P, Dorée M. Dephosphorylation and activation of a p34cdc2/cyclin B complex in vitro by human CDC25 protein. Nature. 1991 May 16;351(6323):242–245. [PubMed]
  • Streuli M, Krueger NX, Thai T, Tang M, Saito H. Distinct functional roles of the two intracellular phosphatase like domains of the receptor-linked protein tyrosine phosphatases LCA and LAR. EMBO J. 1990 Aug;9(8):2399–2407. [PubMed]
  • Studier FW, Rosenberg AH, Dunn JJ, Dubendorff JW. Use of T7 RNA polymerase to direct expression of cloned genes. Methods Enzymol. 1990;185:60–89. [PubMed]
  • Tung HY, Resink TJ, Hemmings BA, Shenolikar S, Cohen P. The catalytic subunits of protein phosphatase-1 and protein phosphatase 2A are distinct gene products. Eur J Biochem. 1984 Feb 1;138(3):635–641. [PubMed]
  • Walker DH, DePaoli-Roach AA, Maller JL. Multiple roles for protein phosphatase 1 in regulating the Xenopus early embryonic cell cycle. Mol Biol Cell. 1992 Jun;3(6):687–698. [PMC free article] [PubMed]
  • Walker DH, Maller JL. Role for cyclin A in the dependence of mitosis on completion of DNA replication. Nature. 1991 Nov 28;354(6351):314–317. [PubMed]

Articles from Molecular Biology of the Cell are provided here courtesy of American Society for Cell Biology