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Detection of Protein Ubiquitination
Published on: August 19, 2009
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一个单一的基因因子,负责内细胞蛋白中的泛素识别和单一泛素化
Simona Polo1, Sara Sigismund, Mario Faretta
1Department of Experimental Oncology, European Institute of Oncology, Via Ripamonti 435, 20141, Milan, Italy.
Nature
|March 29, 2002
概括
单基化是一种关键的蛋白质修饰,在像Eps15.15这样的内细胞蛋白中由基相互作用基因 (UIM) 介导. 这种UIM有助于ubiquitin识别和monoubiquitination,形成一个新的细胞内网络.
科学领域:
- 细胞生物学 细胞生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 乌比基化是一种关键的翻译后修改,涉及将乌比基添加到蛋白质中,导致多基化 (蛋白质降解) 或单基化 (功能不太清楚).
- 单双化在膜贩运中的作用,特别是酵母,是一个新兴的研究领域.
- 内细胞蛋白在涉及膜动态的细胞过程中起着至关重要的作用.
研究的目的:
- 为了确定在内细胞蛋白中负责单双化的特定蛋白质序列.
- 调查这些序列在泛素识别和修改中的功能.
- 阐明由这些相互作用在内细胞通路中形成的潜在网络.
主要方法:
- 对单基化内细胞蛋白 (Eps15,eps15R) 的碳氧终端氨基酸序列的分析.
- 鉴定和表征与无处不在素相互作用的基因 (UIM).
- 实验证实UIM在多种内细胞蛋白 (Eps15,eps15R,epsins,Hrs) 的泛素结合和单泛素化中的作用.
主要成果:
- 在Eps15和eps15R的碳氧末端保留了一个短的氨基酸延伸,这对于它们的单双化是必不可少的.
- 这一序列构成了UIM,它也存在于其他内细胞蛋白质 (epsins,Hrs) 中,并且是单双化所必需的.
- Eps15,eps15R,epsins和Hrs的UIM直接结合于无处不在素,证实了它们在识别中的作用.
- 在这些蛋白质中,相同的UIM动机负责无素识别和单素化.
结论:
- 在几个内细胞蛋白质中,UIM基因是单基因化的一个关键决定因素.
- 这些发现预测了一个新的UIM:基于ubiquitin的细胞内网络.
- Eps15/eps15R,epsins和Hrs可以充当连接ubiquitinated货物的适配器,将其与内细胞机械连接起来,并通过自我-monoubiquitination潜在地放大网络.
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