在TRIM蛋白家族中的RING E3伪酶的鉴定
Jane Dudley-Fraser1, Diego Esposito1, Katherine A McPhie1
1Molecular Structure of Cell Signalling Laboratory, The Francis Crick Institute, London, UK.
Nature communications
|April 11, 2025
概括
一些TRIpartite Motif (TRIM) 蛋白质作为伪酶起作用,由于其RING域的结构变化,缺乏全方位素E3酶活性. 这一发现影响了对TRIM蛋白在细胞过程和疾病中的功能的理解.
科学领域:
- 生物化学 生化学
- 分子生物学分子生物学
- 结构生物学 结构生物学
背景情况:
- 三分基因 (TRIM) 蛋白对多种细胞功能至关重要,通常归因于它们由RING域介导的无素E3结合酶活性.
- 然而,一些具有RING域的TRIM蛋白不表现出可检测的无处不在活性,这表明了替代功能或调节机制.
研究的目的:
- 综合分析整个TRIM蛋白家族的全域Ubiquitin E3结合酶活性和RING域结构.
- 识别可能没有正规酶活性的TRIM蛋白,并研究其结构基础.
- 探索这些发现对理解TRIM蛋白在细胞生理学和疾病中的作用的影响.
主要方法:
- 对TRIM蛋白家族进行了集成的in-cellulo,in-vitro和in-silico结构功能分析.
- 详细检查RING域结构特征,包括同质化和E2~ubiquitin接口.
- 功能性试验,以评估乌比奎E3结合酶活性和乌比奎转移催化.
主要成果:
- 鉴定出几种TRIM蛋白质是"伪酶",缺乏可检测的ubiquitin E3酶活性.
- 在这些伪酶的RING域中,在关键接口 (同位体化或E2~ubiquitin结合) 观察到结构差异.
- 这些结构变化破坏了催化能力转移ubiquitin.
结论:
- TRIM蛋白家族包含具有分歧的RING域结构的成员,这些结构会损害连酶活性,将它们分类为伪连酶.
- 这些发现挑战了所有TRIM蛋白质对E3酶活性的普遍假设.
- 这项研究为研究TRIM蛋白质在健康和疾病中的非酶功能开辟了新的途径.
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