CRISPR相关转座酶及其细菌基因组编辑应用

CRISPR-associated Transposases and Their Applications in Bacterial Genome Editing

CRISPR-Cas能够在RNA引导下靶向DNA或RNA的特定序列,改变RNA序列即可改变靶向位点,利用这一可重编程特性已开发出了各种强大的遗传学工具。最近发现CRISPR元件在进化过程中被Tn7转座子劫持,由此衍生出的CRISPR相关转座酶(CRISPR-associated transposases, CASTs)系统具有RNA引导DNA整合的能力,被部署为靶点可重编程的基因组整合工具,在大片段和多重基因整合上具有广阔的应用前景。本文追溯了CASTs的发现历程,总结了不同类型CASTs的基因座结构特点、介导基因整合的机制模型以及其在多种革兰氏阴性细菌中的部署和应用。

CRISPR-Cas can target a specific sequence of DNA or RNA guided by a short RNA guide.The target sites can be changed with the RNA sequences.A variety of powerful genetic tools have been developed based on this reprogramming property.Recently,it has been found that some CRISPR elements are captured by Tn7 transposons during evolution,the derived CRISPR-associated transposases(CASTs)system has the ability of RNA-guided DNA integration.Some of them has been deployed as programmable genome integration tools,which have broad application prospects in large fragments and multiple gene integration.This review traces the discovery of CASTs,summarizes the characteristics of different types of CASTs loci,the mechanism models of gene integration,and their deployments and applications in a variety of Gram-negative bacteria.