定量蛋白质组学揭示了非传统的无素链在蛋白质体降解中的功能
Ping Xu1, Duc M Duong, Nicholas T Seyfried
1Department of Human Genetics, Center for Neurodegenerative Diseases, Emory University, Atlanta, GA 30322, USA.
Cell
|April 7, 2009
概括
除了K48和K63链接之外,非常规的聚比基因链对于蛋白质降解和细胞功能至关重要. 这些非K63链,包括K11链接,在诸如内质网膜相关降解 (ERAD) 等途径中发挥关键作用.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
背景情况:
- 乌比基的修饰调节了蛋白质的功能和降解.
- 聚比奎丁链对蛋白质体降解 (K48) 或非蛋白质分解功能 (K63) 的信号.
- 其他聚比奎丁链接 (K6,K11,K27,K29,K33) 的作用在很大程度上仍未被描述.
研究的目的:
- 为了研究非传统的多比基链的体内丰度和功能.
- 为了确定由非K63无素链接调节的基质和通路.
- 阐明K11结合的多比基链在细胞过程中的特定作用.
主要方法:
- 基于定量质谱的蛋白质组学,以分析酵母蛋白质和无处不在的蛋白质.
- 野生型和Ubiquitin K11R突变酵母菌株的比较.
- 识别K11链接特定基质.
主要成果:
- 非K63聚比基因链接在体内丰富,可能针对蛋白质进行降解.
- 单独与K48结合的无素对酵母活力是不够的,这表明不同结合的功能部分冗余.
- 连接K11链的特点是Ubc6,这是细胞内膜网膜相关降解 (ERAD) 中的关键酶.
结论:
- 非传统的多比基因链对比基因-蛋白酶体系统至关重要.
- 与K11结合的多比奎链在ERAD途径中发挥着重要作用.
- 了解各种各样的泛素联系对于理解蛋白质平衡和细胞调节至关重要.
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