在触发因素伴侣的折叠和组装活动中识别杂乱的基板
Erik Martinez-Hackert1, Wayne A Hendrickson
1Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA.
Cell
|September 10, 2009
概括
触发因子 (TF) 是一个分子伴侣. 没有核糖体的TF拯救了170多种蛋白质的错误折叠,揭示了其在蛋白质平衡和复杂组装中的广泛细胞质作用.
科学领域:
- 细菌蛋白质的合成和折叠.
- 分子的陪伴者和蛋白质的平衡.
背景情况:
- 触发因子 (TF) 是一种已知与核糖体上新生多链相互作用的细菌分子伴侣.
- 在细胞质中, ribo-free TF 的活性和基质特异性仍然不那么明显.
- 实验室研究表明,TF在促进蛋白质重新折叠中的作用.
研究的目的:
- 为了研究细菌细胞质中无核糖体TF的功能.
- 为了确定与细胞质TF相互作用并被细胞质TF拯救的全长蛋白质的范围.
- 阐明TF与生理基质相互作用的结构基础.
主要方法:
- 蛋白质组分析以确定埃舍里希亚大肠杆菌中细胞质TF基质.
- 来自Thermotoga maritima的TF:S7复合物的生物化学表征.
- 进行X射线晶体学以确定TF:S7复合物的原子结构.
主要成果:
- 没有核糖体的TF稳定地与170多个全长蛋白质结合并从错误折叠中拯救它们.
- 核糖体蛋白S7被确定为细胞质TF基质.
- TF:S7复合体的晶体结构为基质识别和伴侣机制提供了原子层的洞察力.
结论:
- 细胞质TF具有广泛的基质谱,充当一个散乱的陪伴者.
- TF在维持蛋白质平衡和防止细菌细胞质中错误折叠方面发挥着重要作用.
- TF:S7复合体结构揭示了基质结合的机制,并表明TF参与了蛋白质复合体生物发生.
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