Morgridge Institute for Research, Madison, WI 53715.
Proc Natl Acad Sci U S A. 2013 Sep 24;110(39):15644-9. doi: 10.1073/pnas.1313587110. Epub 2013 Aug 12.
Genome engineering in human pluripotent stem cells (hPSCs) holds great promise for biomedical research and regenerative medicine. Recently, an RNA-guided, DNA-cleaving interference pathway from bacteria [the type II clustered, regularly interspaced, short palindromic repeats (CRISPR)-CRISPR-associated (Cas) pathway] has been adapted for use in eukaryotic cells, greatly facilitating genome editing. Only two CRISPR-Cas systems (from Streptococcus pyogenes and Streptococcus thermophilus), each with their own distinct targeting requirements and limitations, have been developed for genome editing thus far. Furthermore, limited information exists about homology-directed repair (HDR)-mediated gene targeting using long donor DNA templates in hPSCs with these systems. Here, using a distinct CRISPR-Cas system from Neisseria meningitidis, we demonstrate efficient targeting of an endogenous gene in three hPSC lines using HDR. The Cas9 RNA-guided endonuclease from N. meningitidis (NmCas9) recognizes a 5'-NNNNGATT-3' protospacer adjacent motif (PAM) different from those recognized by Cas9 proteins from S. pyogenes and S. thermophilus (SpCas9 and StCas9, respectively). Similar to SpCas9, NmCas9 is able to use a single-guide RNA (sgRNA) to direct its activity. Because of its distinct protospacer adjacent motif, the N. meningitidis CRISPR-Cas machinery increases the sequence contexts amenable to RNA-directed genome editing.
人多能干细胞(hPSCs)中的基因组工程在生物医学研究和再生医学方面具有广阔的前景。最近,一种源自细菌的 RNA 引导、DNA 切割干扰途径(II 型簇状、规则间隔、短回文重复序列(CRISPR)-CRISPR 相关(Cas)途径)已被用于真核细胞,极大地促进了基因组编辑。迄今为止,只有两种 CRISPR-Cas 系统(来自化脓性链球菌和嗜热链球菌)被开发用于基因组编辑,每个系统都有其独特的靶向要求和限制。此外,关于这些系统在 hPSCs 中使用长供体 DNA 模板的同源定向修复(HDR)介导的基因靶向,信息有限。在这里,我们使用脑膜炎奈瑟菌的一种独特的 CRISPR-Cas 系统,通过 HDR 证明了在三种 hPSC 系中对一个内源性基因的有效靶向。来自脑膜炎奈瑟菌的 Cas9 RNA 引导内切酶(NmCas9)识别与来自化脓性链球菌和嗜热链球菌的 Cas9 蛋白(SpCas9 和 StCas9,分别)识别的不同的 5'-NNNNGATT-3' 前导序列相邻基序(PAM)。与 SpCas9 相似,NmCas9 能够使用单引导 RNA(sgRNA)来指导其活性。由于其独特的前导序列相邻基序,脑膜炎奈瑟菌的 CRISPR-Cas 机制增加了可用于 RNA 指导的基因组编辑的序列上下文。