Abstract
The product of the cdc2 gene (cdc2 or p34cdc2), the catalytic subunit of M phase-promoting factor (MPF), is held at a constant steady-state level throughout the cell cycle. In this report, we show that the constant concentration is maintained by a coordinated regulation of protein synthesis and degradation. At the end of each mitosis, cdc2 transcription is shut off, and the mRNA is rapidly degraded. A 12-fold activation of cdc2 gene transcription occurs every round of the cell cycle at the G1/S transition, in a growth factor-dependent manner. The increase in mRNA correlates with the accumulation of newly synthesized cdc2 during S and G2 phases. At the onset of mitosis, the translation of cdc2 mRNA is shut off. During G1 phase, the cdc2 protein has a relatively long half-life of 18 hr, so cdc2 made in the previous cell cycle is maintained. Once synthesis is activated at G1/S, a concurrent mechanism of degradation is activated, and the protein half-life is reduced to 7.5 hr. By the end of interphase, new cdc2 accounts for 75-85% of the total cdc2 pool. In addition, we show that greater than 75% of the new cdc2 complexes with cyclin, suggesting that a majority of the new cdc2 functions as MPF.
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Selected References
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- Broek D., Bartlett R., Crawford K., Nurse P. Involvement of p34cdc2 in establishing the dependency of S phase on mitosis. Nature. 1991 Jan 31;349(6308):388–393. doi: 10.1038/349388a0. [DOI] [PubMed] [Google Scholar]
- Chomczynski P., Sacchi N. Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction. Anal Biochem. 1987 Apr;162(1):156–159. doi: 10.1006/abio.1987.9999. [DOI] [PubMed] [Google Scholar]
- Draetta G., Beach D. Activation of cdc2 protein kinase during mitosis in human cells: cell cycle-dependent phosphorylation and subunit rearrangement. Cell. 1988 Jul 1;54(1):17–26. doi: 10.1016/0092-8674(88)90175-4. [DOI] [PubMed] [Google Scholar]
- Draetta G., Beach D. The mammalian cdc2 protein kinase: mechanisms of regulation during the cell cycle. J Cell Sci Suppl. 1989;12:21–27. doi: 10.1242/jcs.1989.supplement_12.3. [DOI] [PubMed] [Google Scholar]
- 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. doi: 10.1038/336738a0. [DOI] [PubMed] [Google Scholar]
- Durkacz B., Carr A., Nurse P. Transcription of the cdc2 cell cycle control gene of the fission yeast Schizosaccharomyces pombe. EMBO J. 1986 Feb;5(2):369–373. doi: 10.1002/j.1460-2075.1986.tb04221.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Furukawa Y., Piwnica-Worms H., Ernst T. J., Kanakura Y., Griffin J. D. cdc2 gene expression at the G1 to S transition in human T lymphocytes. Science. 1990 Nov 9;250(4982):805–808. doi: 10.1126/science.2237430. [DOI] [PubMed] [Google Scholar]
- Gould K. L., Nurse P. Tyrosine phosphorylation of the fission yeast cdc2+ protein kinase regulates entry into mitosis. Nature. 1989 Nov 2;342(6245):39–45. doi: 10.1038/342039a0. [DOI] [PubMed] [Google Scholar]
- Lee M. G., Norbury C. J., Spurr N. K., Nurse P. Regulated expression and phosphorylation of a possible mammalian cell-cycle control protein. Nature. 1988 Jun 16;333(6174):676–679. doi: 10.1038/333676a0. [DOI] [PubMed] [Google Scholar]
- Lee M. G., Nurse P. Complementation used to clone a human homologue of the fission yeast cell cycle control gene cdc2. Nature. 1987 May 7;327(6117):31–35. doi: 10.1038/327031a0. [DOI] [PubMed] [Google Scholar]
- McGowan C. H., Russell P., Reed S. I. Periodic biosynthesis of the human M-phase promoting factor catalytic subunit p34 during the cell cycle. Mol Cell Biol. 1990 Jul;10(7):3847–3851. doi: 10.1128/mcb.10.7.3847. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Moreno S., Hayles J., Nurse P. Regulation of the cell cycle timing of mitosis. J Cell Sci Suppl. 1989;12:1–8. doi: 10.1242/jcs.1989.supplement_12.1. [DOI] [PubMed] [Google Scholar]
- Morla A. O., Draetta G., Beach D., Wang J. Y. Reversible tyrosine phosphorylation of cdc2: dephosphorylation accompanies activation during entry into mitosis. Cell. 1989 Jul 14;58(1):193–203. doi: 10.1016/0092-8674(89)90415-7. [DOI] [PubMed] [Google Scholar]
- Morris G. F., Mathews M. B. Regulation of proliferating cell nuclear antigen during the cell cycle. J Biol Chem. 1989 Aug 15;264(23):13856–13864. [PubMed] [Google Scholar]
- Murray A. W., Kirschner M. W. Cyclin synthesis drives the early embryonic cell cycle. Nature. 1989 May 25;339(6222):275–280. doi: 10.1038/339275a0. [DOI] [PubMed] [Google Scholar]
- Nurse P., Bissett Y. Gene required in G1 for commitment to cell cycle and in G2 for control of mitosis in fission yeast. Nature. 1981 Aug 6;292(5823):558–560. doi: 10.1038/292558a0. [DOI] [PubMed] [Google Scholar]
- Osmani S. A., May G. S., Morris N. R. Regulation of the mRNA levels of nimA, a gene required for the G2-M transition in Aspergillus nidulans. J Cell Biol. 1987 Jun;104(6):1495–1504. doi: 10.1083/jcb.104.6.1495. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pardee A. B. G1 events and regulation of cell proliferation. Science. 1989 Nov 3;246(4930):603–608. doi: 10.1126/science.2683075. [DOI] [PubMed] [Google Scholar]
- Pines J., Hunter T. Human cyclin A is adenovirus E1A-associated protein p60 and behaves differently from cyclin B. Nature. 1990 Aug 23;346(6286):760–763. doi: 10.1038/346760a0. [DOI] [PubMed] [Google Scholar]
- Pines J., Hunter T. Isolation of a human cyclin cDNA: evidence for cyclin mRNA and protein regulation in the cell cycle and for interaction with p34cdc2. Cell. 1989 Sep 8;58(5):833–846. doi: 10.1016/0092-8674(89)90936-7. [DOI] [PubMed] [Google Scholar]
- Pines J., Hunter T. p34cdc2: the S and M kinase? New Biol. 1990 May;2(5):389–401. [PubMed] [Google Scholar]
- Sadhu K., Reed S. I., 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. doi: 10.1073/pnas.87.13.5139. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Solomon M. J., Glotzer M., Lee T. H., Philippe M., Kirschner M. W. Cyclin activation of p34cdc2. Cell. 1990 Nov 30;63(5):1013–1024. doi: 10.1016/0092-8674(90)90504-8. [DOI] [PubMed] [Google Scholar]
- Th'ng J. P., Wright P. S., Hamaguchi J., Lee M. G., Norbury C. J., Nurse P., Bradbury E. M. The FT210 cell line is a mouse G2 phase mutant with a temperature-sensitive CDC2 gene product. Cell. 1990 Oct 19;63(2):313–324. doi: 10.1016/0092-8674(90)90164-a. [DOI] [PubMed] [Google Scholar]
- Tobey R. A., Valdez J. G., Crissman H. A. Synchronization of human diploid fibroblasts at multiple stages of the cell cycle. Exp Cell Res. 1988 Dec;179(2):400–416. doi: 10.1016/0014-4827(88)90279-0. [DOI] [PubMed] [Google Scholar]