Clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated (Cas) genes provide adaptive immunity against invasion of foreign nucleic acids in archaea and bacteria. The system functions in three distinct stages: adaptation, biogenesis, and interference. CRISPR-Cas systems are currently classified into at least five different types, each with a signature protein among which Type III systems exhibit a dual DNA/RNA interference activity. Structures of a few Type III surveillance complexes have been determined: they are composed of several different subunits and exhibit striking architectural similarities to Type I surveillance complexes. Here, we review the genetic, biochemical, and structural studies concerning CRISPR-Cas Type III systems and discuss their application for genetic manipulations, including genome engineering and gene silencing.

中文翻译：

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III 型 CRISPR-Cas 系统：简介及其在遗传操作中的应用。


成簇的规则间隔的短回文重复序列 (CRISPR) 和 CRISPR 相关 (Cas) 基因提供了针对古细菌和细菌中外来核酸入侵的适应性免疫。该系统在三个不同的阶段发挥作用：适应、生物发生和干扰。 CRISPR-Cas系统目前分为至少五种不同类型，每种类型都有一个特征蛋白，其中III型系统表现出双重DNA/RNA干扰活性。一些 III 型监视综合体的结构已经确定：它们由几个不同的子单元组成，并与 I 型监视综合体在结构上表现出惊人的相似性。在这里，我们回顾了有关 CRISPR-Cas III 型系统的遗传、生化和结构研究，并讨论了它们在基因操作（包括基因组工程和基因沉默）中的应用。