CRISPR/Cas系统在谱系追踪中的应用

The Application of CRISPR/Cas System in Lineage Tracing

CRISPR/Cas系统是细菌和古生菌的自适应免疫系统,其对基因组高效精准的编辑,极大地推动了发育生物学、表观遗传学、药物开发、疾病治疗等多个学科和研究领域的发展.CRISPR/Cas9系统诱导基因组DNA产生双链断裂,以非同源末端连接(non-homologous end joining,NHEJ)的方式进行修复,因此会在剪切位置随机地引入短的插入和删除(insertions and deletions,indels).这些引入的indels作为区分细胞的标签,被称为条形码.细胞条形码技术已经被用于谱系追踪、基因组功能筛选等.而测序技术的飞速发展和成本的大幅度降低以及单细胞转录组测序技术的出现,可以在时间和空间层面同时对数百万个单细胞进行谱系追踪,记录细胞活动.本综述讨论了CRISPR/Cas系统的工作原理、细胞条形码技术和单细胞测序技术(scRNA-seq),以及两者结合产生的单细胞谱系追踪技术.

CRISPR/Cas system is an adaptive immune system of bacteria and archaea.By virtue of its efficient and accurate editing of the genome,it has greatly promoted the development of multiple disciplines and research fields such as developmental biology,epigenetics,drug research and disease treatment.The CRISPR/Cas9 system induces double strand breaks in genomic DNA that are repaired in the form of non-homologous terminal ligations(NHEJ),thereby introducing short,random insertions and deletions(indels)at the cut sites.These introduced indels can be used to distinguish cells,that is,cellular labels-termed barcodes.Cell barcoding has been used for lineage tracing,genome functional screening and so on.With the rapid development of sequencing technology and the substantial reduction of cost,as well as the emergence of single-cell transcriptome sequencing(scRNA-seq)technology,millions of single cells can be simultaneously tracked at the time and space level to record cell activities.In this review,the working principle of the CRISPR/Cas system,cell barcoding and scRNA-seq,as well as the single-cell lineage tracing technology produced by the combination of the two are discussed.