M-phase inducer phosphatase 1 also known as dual specificity phosphatase Cdc25A is a protein that in humans is encoded by the cell division cycle 25 homolog A (CDC25A) gene.
All mammals examined to date have three homologues of the ancestral Cdc25 gene (found e.g. in the fungus species S. pombe , designated Cdc25A, Cdc25B, and Cdc25C. In contrast, some invertebrates harbour 2 (e.g., the Drosophila proteins String and Twine) or four (e.g., C. elegans Cdc-25.1 - Cdc-25.4) homologues.
CDC25A is required for progression from G1 to the S phase of the cell cycle, but also plays roles in later cell cycle events. In particular, it is stabilized in metaphase cells and is degraded upon metaphase exit akin to Cyclin B. It is competent to activate the G1/S cyclin-dependent kinases CDK4 and CDK2 by removing inhibitory phosphate groups from adjacent tyrosine and threonine residues; it can also activate Cdc2 (Cdk1), the principal mitotic Cdk.
Involvement in cancer
CDC25A is specifically degraded in response to DNA damage, resulting in cell cycle arrest. Thus, this degradation represents one axis of a DNA damage checkpoint, complementing induction of p53 and p21 in the inhibition of CDKs.
CDC25A is considered an oncogene, as it can cooperate with oncogenic RAS to transform rodent fibroblasts, and it is overexpressed in tumours from a variety of tissues, including breast and head & neck tumours. It is a target of the E2F family of transcription factors. Therefore, its overexpression is a common consequence of dysregulation of the p53-p21-Cdk axis in carcinogenesis.[1]
↑Galaktionov K, Jessus C, Beach D (May 1995). "Raf1 interaction with Cdc25 phosphatase ties mitogenic signal transduction to cell cycle activation". Genes Dev. 9 (9): 1046–58. doi:10.1101/gad.9.9.1046. PMID7744247.
↑Huang TS, Shu CH, Yang WK, Whang-Peng J (Jul 1997). "Activation of CDC 25 phosphatase and CDC 2 kinase involved in GL331-induced apoptosis". Cancer Res. 57 (14): 2974–8. PMID9230211.
↑Goloudina A, Yamaguchi H, Chervyakova DB, Appella E, Fornace AJ, Bulavin DV (2003). "Regulation of human Cdc25A stability by Serine 75 phosphorylation is not sufficient to activate a S phase checkpoint". Cell Cycle. 2 (5): 473–8. doi:10.4161/cc.2.5.482. PMID12963847.
↑Sanchez Y, Wong C, Thoma RS, Richman R, Wu Z, Piwnica-Worms H, Elledge SJ (Sep 1997). "Conservation of the Chk1 checkpoint pathway in mammals: linkage of DNA damage to Cdk regulation through Cdc25". Science. 277 (5331): 1497–501. doi:10.1126/science.277.5331.1497. PMID9278511.
↑Xu X, Burke SP (Mar 1996). "Roles of active site residues and the NH2-terminal domain in the catalysis and substrate binding of human Cdc25". J. Biol. Chem. 271 (9): 5118–24. doi:10.1074/jbc.271.9.5118. PMID8617791.
↑Wang Z, Wang M, Lazo JS, Carr BI (May 2002). "Identification of epidermal growth factor receptor as a target of Cdc25A protein phosphatase". J. Biol. Chem. 277 (22): 19470–5. doi:10.1074/jbc.M201097200. PMID11912208.
↑Mochizuki T, Kitanaka C, Noguchi K, Muramatsu T, Asai A, Kuchino Y (Jun 1999). "Physical and functional interactions between Pim-1 kinase and Cdc25A phosphatase. Implications for the Pim-1-mediated activation of the c-Myc signaling pathway". J. Biol. Chem. 274 (26): 18659–66. doi:10.1074/jbc.274.26.18659. PMID10373478.
Kerkhoff E, Rapp UR (1998). "Cell cycle targets of Ras/Raf signalling". Oncogene. 17 (11 Reviews): 1457–62. doi:10.1038/sj.onc.1202185. PMID9779991.
Nilsson I, Hoffmann I (2000). "Cell cycle regulation by the Cdc25 phosphatase family". Progress in cell cycle research. 4: 107–14. doi:10.1007/978-1-4615-4253-7_10. PMID10740819.
Galaktionov K, Beach D (1992). "Specific activation of cdc25 tyrosine phosphatases by B-type cyclins: evidence for multiple roles of mitotic cyclins". Cell. 67 (6): 1181–94. doi:10.1016/0092-8674(91)90294-9. PMID1836978.
Galaktionov K, Lee AK, Eckstein J, Draetta G, Meckler J, Loda M, Beach D (1995). "CDC25 phosphatases as potential human oncogenes". Science. 269 (5230): 1575–7. doi:10.1126/science.7667636. PMID7667636.
Galaktionov K, Jessus C, Beach D (1995). "Raf1 interaction with Cdc25 phosphatase ties mitogenic signal transduction to cell cycle activation". Genes Dev. 9 (9): 1046–58. doi:10.1101/gad.9.9.1046. PMID7744247.
Demetrick DJ, Beach DH (1994). "Chromosome mapping of human CDC25A and CDC25B phosphatases". Genomics. 18 (1): 144–7. doi:10.1006/geno.1993.1440. PMID8276402.
Xu X, Burke SP (1996). "Roles of active site residues and the NH2-terminal domain in the catalysis and substrate binding of human Cdc25". J. Biol. Chem. 271 (9): 5118–24. doi:10.1074/jbc.271.9.5118. PMID8617791.
Huang TS, Shu CH, Yang WK, Whang-Peng J (1997). "Activation of CDC 25 phosphatase and CDC 2 kinase involved in GL331-induced apoptosis". Cancer Res. 57 (14): 2974–8. PMID9230211.
Fauman EB, Cogswell JP, Lovejoy B, Rocque WJ, Holmes W, Montana VG, Piwnica-Worms H, Rink MJ, Saper MA (1998). "Crystal structure of the catalytic domain of the human cell cycle control phosphatase, Cdc25A". Cell. 93 (4): 617–25. doi:10.1016/S0092-8674(00)81190-3. PMID9604936.
Sexl V, Diehl JA, Sherr CJ, Ashmun R, Beach D, Roussel MF (1999). "A rate limiting function of cdc25A for S phase entry inversely correlates with tyrosine dephosphorylation of Cdk2". Oncogene. 18 (3): 573–82. doi:10.1038/sj.onc.1202362. PMID9989807.
Mochizuki T, Kitanaka C, Noguchi K, Muramatsu T, Asai A, Kuchino Y (1999). "Physical and functional interactions between Pim-1 kinase and Cdc25A phosphatase. Implications for the Pim-1-mediated activation of the c-Myc signaling pathway". J. Biol. Chem. 274 (26): 18659–66. doi:10.1074/jbc.274.26.18659. PMID10373478.