Fig. 1
From: CRISPR/Cas: a potential gene-editing tool in the nervous system
Schematic diagrams of the engineered Cas protein. a Base editors mediated by dead Cas9 (dCas9) with the separate fusion of the rat cytidine deaminase APOBEC1 and adenine deaminase TadA. b Specific epigenomic modification tools generated by dCas9 respectively fused with histone acetyltransferase P300, ten-eleven translocation methylcytosine dioxygenase 1 (Tet1) and lysine-specific histone demethylase 1 (LSD1). c Different CRISPR activation (CRISPRa) tools. Fusing three transcriptional activators VP64, p65 and Rta to the dCas protein at the same time can successfully activate multigene expression (left). Fusing two RNA hairpin aptamers which bind to dimers of the bacteriophage MS2 coat proteins and additional activators such as p65 and the human heat shock factor 1 (HSF1) to sgRNA can recruit more activation molecules (middle). Fusing 10 repeats of scFv (an activator module single-chain variable fragment) /p65/HSF1 to the dCas9 protein can more efficiently active multigene expression (right)