U.S. Department of Energy-Joint Genome Institute, Walnut Creek, CA, USA.
RNA Biol. 2013 May;10(5):687-93. doi: 10.4161/rna.24571. Epub 2013 Apr 11.
Members of the phylum Cyanobacteria inhabit ecologically diverse environments. However, the CRISPR-Cas (clustered regularly interspaced short palindromic repeats, CRISPR associated genes), an extremely adaptable defense system, has not been surveyed in this phylum. We analyzed 126 cyanobacterial genomes and, surprisingly, found CRISPR-Cas in the majority except the marine subclade (Synechococcus and Prochlorococcus), in which cyanophages are a known force shaping their evolution. Multiple observations of CRISPR loci in the absence of cas1/cas2 genes may represent an early stage of losing a CRISPR-Cas locus. Our findings reveal the widespread distribution of their role in the phylum Cyanobacteria and provide a first step to systematically understanding CRISPR-Cas systems in cyanobacteria.
蓝藻门的成员栖息在生态多样的环境中。然而，CRISPR-Cas（成簇的规律间隔短回文重复序列，CRISPR 相关基因）是一种极其适应性强的防御系统，在这个门中尚未进行调查。我们分析了 126 个蓝藻基因组，令人惊讶的是，除了海洋亚群（聚球藻和原绿球藻）之外，大多数蓝藻都发现了 CRISPR-Cas，而在这些亚群中，噬藻体是塑造它们进化的已知力量。在没有 cas1/cas2 基因的情况下，CRISPR 基因座的多次观察可能代表失去 CRISPR-Cas 基因座的早期阶段。我们的发现揭示了它们在蓝藻门中的广泛分布，并为系统地了解蓝藻中的 CRISPR-Cas 系统提供了第一步。
