The schematic of CRISPR Mediated Microbe Genome Editing (Wang, et al. 2016)

Found in bacteria and archaebacteria, the regular cluster-interval short palindromic repeat (CRISPR) can effectively resist the invasion and insertion of phage and various gene elements at the gene level. CRISPR-Associate (Cas) protein is a kind of RNA-mediated double-stranded DNA endonuclease which own the ability to cleave exogenous DNA. 

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