Innovative Genomics Institute, University of California, Berkeley, Berkeley, CA, USA.
Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA, USA.
Science. 2020 Jul 17;369(6501):333-337. doi: 10.1126/science.abb1400.
CRISPR-Cas systems are found widely in prokaryotes, where they provide adaptive immunity against virus infection and plasmid transformation. We describe a minimal functional CRISPR-Cas system, comprising a single ~70-kilodalton protein, CasΦ, and a CRISPR array, encoded exclusively in the genomes of huge bacteriophages. CasΦ uses a single active site for both CRISPR RNA (crRNA) processing and crRNA-guided DNA cutting to target foreign nucleic acids. This hypercompact system is active in vitro and in human and plant cells with expanded target recognition capabilities relative to other CRISPR-Cas proteins. Useful for genome editing and DNA detection but with a molecular weight half that of Cas9 and Cas12a genome-editing enzymes, CasΦ offers advantages for cellular delivery that expand the genome editing toolbox.
CRISPR-Cas 系统广泛存在于原核生物中,它们为病毒感染和质粒转化提供了适应性免疫。我们描述了一个最小的功能性 CRISPR-Cas 系统,该系统由一个单一的约 70 千道尔顿的蛋白质 CasΦ和一个仅在巨大噬菌体基因组中编码的 CRISPR 阵列组成。CasΦ 使用单个活性位点进行 CRISPR RNA(crRNA)加工和 crRNA 引导的 DNA 切割,以靶向外来核酸。与其他 CRISPR-Cas 蛋白相比,这种超紧凑的系统在体外以及在人和植物细胞中具有扩展的靶标识别能力。CasΦ 可用于基因组编辑和 DNA 检测,但分子量是 Cas9 和 Cas12a 基因组编辑酶的一半,它在细胞递送上具有优势,扩展了基因组编辑工具包。