在Listeria monocytogenes的表面,由Arp2/3蛋白质复合物诱导了动氨酸聚合
M D Welch1, A Iwamatsu, T J Mitchison
1Department of Cellular and Molecular Pharmacology, University of California at San Francisco, 94143, USA. welch@cgl.ucsf.edu
Nature
|January 16, 1997
概括
李斯特菌单细胞原生通过主细胞蛋白质复合体驱动的活性聚合来推动自身. 这种复杂的,含有actin相关蛋白质 (ARPs),核化actin组件,使宿主细胞内的细菌运动.
科学领域:
- 细胞生物学 细胞生物学
- 微生物学 微生物学
- 生物化学 生物化学
背景情况:
- 致病细菌,如Listeria monocytogenes,在宿主细胞细胞质中表现出有针对性的运动.
- 细菌的移动性是由细菌表面的活性聚合推动的,形成活性尾巴.
- 了解这种actin聚合机制对于控制细胞actin动态至关重要.
研究的目的:
- 为了阐明Listeria monocytogenes所使用的actin聚合的机制.
- 识别和描述参与ActA依赖性actin组装的宿主细胞因子.
- 研究净化宿主细胞蛋白质复合体在细菌运动中的作用.
主要方法:
- 净化一个八个多的宿主细胞蛋白质复合体.
- 测试纯化复合物的启动ActA依赖性actin聚合的能力.
- 在受感染的组织培养细胞中定位Arp3亚单元.
主要成果:
- 一个纯化的八个多复合体被确定为宿主细胞的活性蛋白聚合因子.
- 这种复合物足以启动ActA依赖性actin聚合,并介导actin尾巴的形成.
- 该复合体含有Arp2和Arp3与活性蛋白相关的蛋白质 (ARP),Arp3定位在细菌表面和活性蛋白尾部.
- 该Arp2/3复合体作为一个模板,核化actin聚合.
结论:
- 纯化的Arp2/3复合物对于Listeria monocytogenes基于actin的运动性至关重要.
- 在活体中,Arp2/3复合体作为活性核形成促进因子起作用.
- 这项研究提供了细菌病原体对actin聚合的调节的见解.
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