由Vibrio揭示的Actin异型特异相互作用VopV的Actin结合重复
Elena Kudryashova1, Mark A B Kreutzberger2, Ewa Niedzialkowska2
1Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210.
概括
动氨酸结合蛋白 (ABP) 可以区分动氨酸异型. 一种细菌效应蛋白,VopV,由于在活性裂中的特定残留物,可以选择性地结合细胞质活性蛋白.
科学领域:
- 分子生物学分子生物学
- 进化生物学 进化生物学
- 结构生物学 结构生物学
背景情况:
- 动蛋白异型表现出最小的物种特异差异,但表现出组织特异差异.
- 据认为,动氨酸结合蛋白 (ABP) 调节动氨酸异形局部化,但区分的机制尚不清楚.
研究的目的:
- 为了研究亚丁和ABPs之间的异构体特异性相互作用的分子基础.
- 了解 *Vibrio* parahaemolyticus 效应器 VopV 如何区分阿克丁异型.
主要方法:
- 利用动因突变发生法来识别关键的残留物,这些残留物涉及到结合特异性.
- 使用冷电子显微镜 (cryo-EM) 来确定VopV-actin复合物的高分辨率结构.
- 使用生物化学测定测量结合亲和力.
主要成果:
- VopV的活性蛋白结合重复 (ABR) 对细胞质活性蛋白具有较低的纳米分子亲和力,明显高于肌肉活性蛋白.
- 位于actin裂深处的异形特异性残留物被确定为这种选择性结合的关键.
- 化EM结构显示了这些残留物介导的独特结合模式.
结论:
- 已经阐明了actin与其结合伙伴之间高度选择性,异型特异性相互作用的机制.
- 这些发现提供了关于actin及其相互作用的演变的见解.
- 这项研究对理解*Vibrio* parahaemolyticus的发病有意义,这种发病依赖于VopV-细胞质动蛋白相互作用.
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