一种新的人类p53异型是ATR-intra-S阶段检查点的重要组成部分
Gabor Rohaly1, Jan Chemnitz, Silke Dehde
1Heinrich-Pette-Institut für Experimentelle Virologie und Immunologie, Universität Hamburg, Martinistrasse 52, D-20251, Hamburg, Germany.
Cell
|July 13, 2005
概括
一种新发现的p53异型,Deltap53,在受损的S相细胞中表现出转录活性. 这种瘤抑制异型激活p21基因,影响细胞周期进展和DNA修复.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 癌症研究 癌症研究
背景情况:
- 瘤抑制蛋白p53以其交换活化特性而闻名.
- 现有的人类p53异型通常被认为是转录不活跃的.
- 在DNA损伤反应中,p53的作用已经得到了很好的证实.
研究的目的:
- 为了研究一种新的p53异型的转录活性,Deltap53.
- 为了确定Deltap53是否拥有独立的交易能力.
- 阐明Deltap53在S相内检查点中的作用.
主要方法:
- 在p53.3中对替代拼接的分析.
- 报告员测试通过p53和Delta53.3来评估主办方的交易.
- 细胞周期分析作为对DNA损伤的反应.
- 西方涂抹检测蛋白质表达和活性.
主要成果:
- 德尔塔53是一种替代拼接的p53异型,表现出转录活性.
- 与p53.3不同,deltap53选择性地对p21和14-3-3西格玛促进体进行交换,而p53.
- 德尔塔53的活性特异于受损的S相细胞和ATR-intra-S相检查点.
- 德尔塔53诱导的p21表达降低了环林A-Cdk活性,减弱了S相进展.
结论:
- 德尔塔53作为一个转录活性瘤抑制剂异型的功能.
- 德尔塔53-p21-环素A-Cdk通路对于解DNA修复和复制至关重要.
- 德尔塔53是ATR-intra-S阶段DNA损伤检查点的重要组成部分.
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