The encoded protein is a homolog of yeast securin proteins, which prevent separins from promoting sister chromatid separation. It is an anaphase-promoting complex (APC) substrate that associates with a separin until activation of the APC. The gene product has transforming activity in vitro and tumorigenic activity in vivo, and the gene is highly expressed in various tumors. The gene product contains 2 PXXP motifs, which are required for its transforming and tumorigenic activities, as well as for its stimulation of basic fibroblast growth factor expression. It also contains a destruction box (D box) that is required for its degradation by the APC. The acidic C-terminal region of the encoded protein can act as a transactivation domain. The gene product is mainly a cytosolic protein, although it partially localizes in the nucleus.[7]
During Mitosis CDK1 phosphorylate PTTG1 at Ser-165.[12] PTTG1 is down-regulated in melanoma cells in response to the cyclin-dependent kinase inhibitor PHA-848125.[13]
^"Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^"Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^Domínguez A, Ramos-Morales F, Romero F, Rios RM, Dreyfus F, Tortolero M, Pintor-Toro JA (Oct 1998). "hpttg, a human homologue of rat pttg, is overexpressed in hematopoietic neoplasms. Evidence for a transcriptional activation function of hPTTG". Oncogene. 17 (17): 2187–93. doi:10.1038/sj.onc.1202140. PMID9811450. S2CID24151303.
^Zhang X, Horwitz GA, Prezant TR, Valentini A, Nakashima M, Bronstein MD, Melmed S (Jan 1999). "Structure, expression, and function of human pituitary tumor-transforming gene (PTTG)". Molecular Endocrinology. 13 (1): 156–66. doi:10.1210/me.13.1.156. PMID9892021.
^Bernal JA, Luna R, Espina A, Lázaro I, Ramos-Morales F, Romero F, Arias C, Silva A, Tortolero M, Pintor-Toro JA (Oct 2002). "Human securin interacts with p53 and modulates p53-mediated transcriptional activity and apoptosis". Nature Genetics. 32 (2): 306–11. doi:10.1038/ng997. PMID12355087. S2CID1770399.
^Caporali S, Alvino E, Levati L, Esposito AI, Ciomei M, Brasca MG, Del Bufalo D, Desideri M, Bonmassar E, Pfeffer U, D'Atri S (Sep 2012). "Down-regulation of the PTTG1 proto-oncogene contributes to the melanoma suppressive effects of the cyclin-dependent kinase inhibitor PHA-848125". Biochemical Pharmacology. 84 (5): 598–611. doi:10.1016/j.bcp.2012.06.004. PMID22704958.
Further reading
Yu R, Melmed S (2004). "Pituitary tumor transforming gene: an update". Molecular Pathology of the Pituitary. Frontiers of Hormone Research. Vol. 32. pp. 175–85. doi:10.1159/000079044. ISBN3-8055-7740-0. PMID15281346.
Kakar SS (1999). "Assignment of the human tumor transforming gene TUTR1 to chromosome band 5q35.1 by fluorescence in situ hybridization". Cytogenetics and Cell Genetics. 83 (1–2): 93–5. doi:10.1159/000015139. PMID9925941. S2CID28589466.
Kakar SS, Jennes L (1999). "Molecular cloning and characterization of the tumor transforming gene (TUTR1): a novel gene in human tumorigenesis". Cytogenetics and Cell Genetics. 84 (3–4): 211–6. doi:10.1159/000015261. PMID10393434. S2CID38980080.
Zou H, McGarry TJ, Bernal T, Kirschner MW (Jul 1999). "Identification of a vertebrate sister-chromatid separation inhibitor involved in transformation and tumorigenesis". Science. 285 (5426): 418–22. doi:10.1126/science.285.5426.418. PMID10411507.
Kakar SS (Nov 1999). "Molecular cloning, genomic organization, and identification of the promoter for the human pituitary tumor transforming gene (PTTG)". Gene. 240 (2): 317–24. doi:10.1016/S0378-1119(99)00446-1. PMID10580151.