了解翻译之外的eEF1翻译延长因子的功能. 一个蛋白质学方法
Boris S Negrutskii1, Larysa V Porubleva2, Agata Malinowska3
1Institute of Molecular Biology and Genetics, Kyiv, Ukraine; Aarhus Institute of Advanced Sciences, Høegh-Guldbergs, Aarhus C, Denmark; Department of Molecular Biology and Genetics, Aarhus University, Universitetsbyen, Aarhus C, Denmark.
Advances in protein chemistry and structural biology
|January 14, 2024
概括
哺乳动物转化因子eEF1A1和eEF1A2在蛋白质合成之外具有不同的细胞作用. 它们独特的相互作用揭示了它们参与各种过程,如染色体重塑和DNA修复,这表明它们具有更广泛的功能.
科学领域:
- 分子生物学分子生物学
- 细胞生物学 细胞生物学
- 生物化学 生物化学
背景情况:
- 哺乳动物翻译延长因子,真核细胞翻译延长因子1A1 (eEF1A1) 和eEF1A2是具有明显组织特异性表达模式的高度同源的异构体.
- 虽然共享翻译功能,但eEF1A1和eEF1A2在细胞局部化和参与瘤发生和病毒复制等过程方面存在差异.
- 假设这些功能区别来自与异形特异性合作伙伴蛋白的相互作用.
研究的目的:
- 为了确定和描述eEF1A1和eEF1A2.2.的异形特异性蛋白相互作用.
- 阐明与每个eEF1A异型相关的独特细胞复合体和过程.
- 为了发现超越翻译延长的eEF1A异型的新型非正规功能.
主要方法:
- 使用已识别的eEF1A1或eEF1A2合作伙伴蛋白的集合.
- 分析了蛋白质相互作用数据,以确定异形特异性细胞复合体和过程.
- 生物信息分析用于将相互作用映射到已知的细胞路径和功能.
主要成果:
- 确定了涉及eEF1A1和eEF1A2在不同的细胞过程中的异形特异性相互作用.
- 证实了不同的eEF1A异型在与行为因相关的复合体,染色质重塑,核糖核酶H2,腺烯酸环酶和Cul3-RING泛素酶复合体以及线粒体转录启动中的参与.
- 揭示了两种异构体在大型核糖体子单元生物发生,mRNA剪接,DNA不匹配修复,26S蛋白酶体活性,P体和外体形成以及蛋白质向膜中的共同参与.
结论:
- eEF1A1和eEF1A2通过异形特异性蛋白相互作用参与不同的细胞过程.
- 这两种异构体在蛋白质生物合成之外的基本细胞活动中起着至关重要的作用,包括RNA处理,DNA修复和蛋白质降解.
- 数据表明,高细胞水平的eEF1A对于高效的翻译和参与广泛的非正规细胞功能至关重要,其中一些功能仍未完全阐明.
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