相关实验视频

Updated: May 10, 2025

Gene Digital Circuits Based on CRISPR-Cas Systems and Anti-CRISPR Proteins

Gene Digital Circuits Based on CRISPR-Cas Systems and Anti-CRISPR Proteins

Published on: October 18, 2022

通过crRNA结构模拟进行RNA介导的CRISPR-Cas13抑制

Victoria M Hayes¹, Jun-Tao Zhang², Mark A Katz¹

¹Department of Microbiology, University of Washington, Seattle, WA, USA.

Science (New York, N.Y.)

|April 24, 2025

概括

研究人员发现了一种新的抗CRISPRRNA (rAcr),称为rAcrVIA1,它抑制了CRISPR-Cas13系统. 这种RNA使用结构模仿,而不是序列相似性来阻断细菌免疫力,扩大已知的抗CRISPR机制的多样性.

科学领域:

分子生物学
微生物遗传学
结构生物学

背景情况:

细菌菌体使用抗CRISPR (ACR) 因子来逃避CRISPR-Cas适应性免疫.
虽然大多数ACR是蛋白质,但RNA ACRs (rAcrs) 已经出现,模仿CRISPR RNAs (crRNAs) 抑制Cas核酶.
了解各种ACR机制对于利用CRISPR-Cas系统至关重要.

研究的目的:

发现和描述针对CRISPR-Cas系统的新型RNA抗CRISPR (rAcrs).
在Listeria seeligeri*中研究一种新发现的等离子体编码的rAcr的抑制机制.
阐明细菌中基于RNA的免疫逃避的结构基础.

主要方法:

来自Listeria seeligeri的塑编码小RNA,rAcrVIA1的识别和克隆.
生物化学测试以确认rAcrVIA1对CRISPR- Cas13系统的抑制活性.
用冷电子显微镜 (cryo-EM) 确定Cas13-rAcrVIA1复合物的结构.

主要成果:

发现了rAcrVIA1,一个阻碍RNA向CRISPR-Cas13系统的等离子体编码小RNA.
结构分析显示,rAcrVIA1的折叠方式与crRNA非常相似.
尽管对crRNA的序列同样性很小,但rAcrVIA1的抑制发生,这表明结构模拟.

结论:

这些发现扩大了已知RNA抗CRISPRs (rAcrs) 的范围.
rAcrVIA1提供了一个由RNA结构模拟介导的免疫对抗的新例.
这一发现突显了细菌和菌体在分子军备竞赛中采用的多种策略.

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CRISPR Gene Editing Tool for MicroRNA Cluster Network Analysis

CRISPR Gene Editing Tool for MicroRNA Cluster Network Analysis

Published on: April 25, 2022

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