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Updated: Jul 1, 2025

Selection-dependent and Independent Generation of CRISPR/Cas9-mediated Gene Knockouts in Mammalian Cells

Selection-dependent and Independent Generation of CRISPR/Cas9-mediated Gene Knockouts in Mammalian Cells

Published on: June 16, 2017

反CRISPR蛋白触发了CRISPR-Cas9表达的爆发,从而增强了菌体的防御能力

Rachael E Workman¹, Marie J Stoltzfus¹, Nicholas C Keith¹

¹Department of Molecular Biology & Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.

|March 1, 2024

概括

当菌体的抗CRISPR蛋白克服Cas9抑制时,细菌的CRISPR-Cas免疫力得到增强. 这种快速的CRISPR-Cas诱导促进了细菌对菌体的生存,并限制了水平基因转移.

科学领域:

微生物学微生物学
分子生物学分子生物学
菌体研究研究菌体研究

背景情况:

克里斯普尔-卡斯系统赋予细菌对菌体的适应性免疫力.
表达往往被压抑以防止自我准,诱导机制不清楚.
在Streptococcus pyogenes中,Cas9既起到免疫效应的作用,也起到CRISPR-Cas的抑制作用.

研究的目的:

研究菌体感染期间CRISPR-Cas诱导的机制.
确定CRISPR-Cas诱导是否为细菌宿主提供生存益处.
探索抗CRISPR蛋白在调节CRISPR-Cas表达中的作用.

主要方法:

在菌体感染期间研究了Streptococcus pyogenes中的CRISPR-Cas表达动态.
利用菌体编码的抗CRISPR蛋白来研究它们对Cas9抑制的影响.
在不同的感染条件下,量化细菌存活率和 lysogeny 水平.

主要成果:

菌体的抗CRISPR蛋白被证明可以缓解Cas9的自我抑制,迅速增加CRISPR-Cas水平.
这种诱导导致在多个菌体感染轮中显著增强细菌的存活率.
观察到CRISPR-Cas诱导减少了溶解生成,从而限制了水平基因转移.

结论:

Cas9作为菌体传感器起作用,启动抗抗CRISPR转录反应.
菌体介导的Cas9抑制缓解是增强细菌免疫力的关键机制.
克里斯普尔-Cas诱导提供了实质性的生存优势,并影响了菌体-宿主动态.

关键词:

CP: 微生物学微生物学克里斯普尔是什么意思?克里斯普尔是什么意思?这是一个反-CRISPR.细菌免疫力细菌免疫力细菌菌体是一种菌体.

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