Macaluso M, Montanari M, Giordano A
Sbarro Institute for Cancer Research and Molecular Medicine, Center of Biotechnology, College of Science and Technology, Temple University, Philadelphia, PA, USA.
Oncogene. 2006 Aug 28;25(38):5263-7. doi: 10.1038/sj.onc.1209680.
The pRb family proteins (pRb1/105, p107, pRb2/p130), collectively referred to as pocket proteins, are believed to function primarily as regulators of the mammalian cell cycle progression, and suppressors of cellular growth and proliferation. In addition, different studies suggest that these pocket proteins are also involved in development and differentiation of various tissues. Several lines of evidence indicate that generally pRb-family proteins function through their effect on the transcription of E2F-regulated genes. In fact, each of Rb family proteins binds to distinct members of the E2F transcription factors, which regulate the expression of genes whose protein products are necessary for cell proliferation and to drive cell-cycle progression. Nevertheless, pocket proteins can affect the G1/S transition through E2F-independent mechanisms. More recently, a broad range of evidences indicate that pRb-family proteins associate with a wide variety of transcription factors and chromatin remodeling enzymes forming transcriptional repressor complexes that control gene expression. This review focuses on the complex regulatory mechanisms by which pRb-family proteins tell genes when to switch on and off.
pRb家族蛋白（pRb1/105、p107、pRb2/p130）统称为口袋蛋白，被认为主要作为哺乳动物细胞周期进程的调节因子以及细胞生长和增殖的抑制因子发挥作用。此外，不同的研究表明这些口袋蛋白也参与各种组织的发育和分化。多项证据表明，一般而言，pRb家族蛋白通过影响E2F调控基因的转录发挥作用。事实上，Rb家族蛋白中的每一种都与E2F转录因子的不同成员结合，这些转录因子调控其蛋白产物对细胞增殖和驱动细胞周期进程所必需的基因的表达。然而，口袋蛋白可通过不依赖E2F的机制影响G1/S转换。最近，大量证据表明pRb家族蛋白与多种转录因子和染色质重塑酶相互作用，形成控制基因表达的转录抑制复合物。本综述重点关注pRb家族蛋白指示基因何时开启和关闭的复杂调控机制。
