Pin1的细胞定位调控Rb蛋白的磷酸化状态

Cellular localization of Pin1 regulates the phosphorylation status of Rb

摘要:

视网膜母细胞瘤蛋白(Rb)在调控细胞增殖和肿瘤的发生发展中起着至关重要的作用。最新的研究结果表明，蛋白异构酶(Pin1)可调控Rb的功能。我们对Pin1和Rb蛋白的细胞定位、Pin1调控Rb磷酸化的相关机制进行了研究。结果表明，沉默Pin1可降低Rb的磷酸化并抑制细胞的增殖；培养的肿瘤细胞和肿瘤组织中，Pin1可定位到细胞质中，而胞质定位的Pin1也可增加Rb的磷酸化。这是Pin1调控Rb功能的一个崭新的方式。

Abstract:

Retinoblastoma tumor-suppressor proteins (Rb) plays a vital role in regulation of cell proliferation and tumor development. Recent research reveals that peptidyl-prolyl isomerase (Pin1) can regulate the function of Rb. In this study, we examined the cellular localization of Pin1 in tumor tissues, and investigated the effects of Pin1 localization on Rb phosphorylation. Our data demonstrated that knockdown of Pin1 result in a decrease of Rb phosphorylation and cellular viability. Pin1 can localize to cytoplasm in cultured tumor cells and tumor tissues, while cytoplasmic Pin1 can increase the phosphorylation of Rb. This is a novel mechanism for Pin1 in regulating Rb function.