细菌在适应噬菌体攻击的过程中,进化了多种防御系统,噬菌体在细菌的选择压力下,也在不断进化反防御策略,双方的这种进化关系与发生机制一直尚不完全清楚.近年在细菌和古细菌中发现一种新的免疫防御系统.即CRISPR-Cas(clustered regularly interspaced short palindromic repeats-CRISPR-associated system)系统.在对其功能和作用机制深入研究的同时,也不断地揭示了细菌和噬菌体之间的共进化关系.为此,文章在介绍原核细胞中CRISPR-Cas系统介导的免疫机制基础上,重点综述了CRISPR系统在细菌和噬菌体进化中的作用.
CRISPR-Cas system and coevolution of bacteria and phages
In response to the challenge from phages, bacteria evolve a number of defense systems against phage invasion.Meanwhile, the phages evolve multiple counter-defense mechanism as well under the selection pressure from bacteria.The evolution relationship between bacteria and phages, as well as the functional mechanism, still remains to be uncovered.A novel immune system, CRISPR-Cas system, has been found in bacteria and archaea recently.With deeply research of the function and mechanism of CRISPR-Cas system, the coevolution relationship between bacteria and phages is becoming clear.In this review, the mechanism of CRISPR-Cas system-mediated immunity in prokaryotes is introduced.In particular,the progress on the role of CRISPR in the coevolution of bacteria and phage is reviewed.