“…In addition to regulating their natural targets, regulatory RNAs such as riboswitches and sRNAs have been structurally redesigned and developed as efficient and independent regulatory tools in prokaryotes to regulate non-natural target gene expression via the canonical or noncanonical regulation mechanism [ [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] , [16] ]. CRISPR RNAs (clustered regularly interspaced short palindromic repeat RNAs), essential components of the bacterial innate immune system against bacteriophage, guide Cas proteins (CRISPR-associated proteins) to targeted DNA or RNA sequences.…”