一种deubiquitinating酶与SIR4相互作用,并调节S. cerevisiae中的沉默
1Department of Microbiology, University of California, San Francisco 94143, USA.
Cell
|August 23, 1996
概括
酵母沉默蛋白SIR2,SIR3和SIR4与一个二基化酶,UBP3.3相互作用. 删除UBP3增强了端粒和交配类型位点附近的基因沉默,揭示了UBP3作为一个沉默抑制剂.
科学领域:
- 分子生物学分子生物学
- 酵母遗传学 酵母遗传学
- 表观遗传学 在表观遗传学中,表观遗传学是指表观遗传学.
背景情况:
- 沉默信息调节器 (SIR) 综合体,包括SIR2,SIR3和SIR4蛋白质,对于酵母中的转录沉默至关重要.
- 这种沉默发生在特定的基因组区域,包括无声交配类型的位置和端粒.
研究的目的:
- 识别与SIR4.4相关的蛋白质.
- 研究SIR4结合蛋白在转录沉默中的作用.
主要方法:
- 用蛋白亲和色谱来分离与SIR4.4相互作用的蛋白质.
- 进行了基因删除分析,以评估UBP3对沉默的影响.
主要成果:
- 发现SIR2,SIR3和两种新型蛋白质 (69和110kDa) 与SIR4密切相关.
- 110kDa的蛋白质被确定为UBP3,这是一个酵母二维基化酶.
- 删除UBP3基因显著改善了端粒和无声交配类型位点的沉默.
结论:
- UBP3 作为酵母中转录沉默的抑制剂.
- UBP3可能调节SIR蛋白复合体的活性或组合.
- 这些发现揭示了控制基因沉默的新型调节机制.
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