Fig. 2
From: Rodent models for psychiatric disorders: problems and promises
Clustered regularly interspaced palindromic repeats/CRISPR-associated endonuclease (CRISPR/Cas9) workflow. The target sequence is followed by a protospacer adjacent motif (PAM) and is targeted via designed guide-ribonucleic acid (gRNA). The Cas9 protein associates with the gRNA and creates targeted double-stranded breaks which can be repaired via the non-homologous end joining (NHEJ) or homology directed repair (HDR) pathways (A). NHEJ can result in insertion or deletion mutations, resulting in non-expressed or non-functional protein. Combined with donor deoxyribonucleic acid (DNA), HDR can reliably insert genetic material into the targeted area. CRISPR/Cas9 can be used to efficiently create mutant mouse lines by injecting gRNA/Cas9 into single-cell embryos, which are transplanted into pseudo pregnant females, resulting in mutant progeny. Alternatively, gRNA/Cas9 can be virally packaged and injected in vivo to achieve some tissue or region-specific gene editing