The retinoblastoma tumor suppressor protein, Rb, regulates cell proliferation by controlling progression through the restriction point within the G1-phase of the cell cycle (1). Rb has three functionally distinct binding domains and interacts with critical regulatory proteins including the E2F family of transcription factors, c-Abl tyrosine kinase and proteins with a conserved LXCXE motif (2-4). Cell cycle-dependent phosphorylation by a CDK inhibits Rb target binding and allows cell cycle progression (5). Rb inactivation and subsequent cell cycle progression likely requires an initial phosphorylation by cyclin D-CDK4/6 followed by cyclin E-CDK2 phosphorylation (6). Specificity of different CDK/cyclin complexes has been observed in vitro (6-8) and cyclin D1 is required for Ser780 phosphorylation in vivo (9).
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9. Geng, Y. et al. (2001) Proc. Natl. Acad. Sci. USA 98, 194-199. 作者: 小菜 时间: 2008-1-9 17:17
The discovery that two suppressor genes, RB and p53, are intimately involved in cell cycle regulation...
The RB protein forms complexes with SV40 T antigen, the transforming protein of SV40 virus (60); adenovirus ElA protein, which is required for adenovirus-induced cell transformation (61); and the E7 protein of human papilloma virus (HPV) (62), which is required for HPVinduced tumor formation. 作者: 闲云 时间: 2008-1-10 10:24
