Fig. 4
From: New insight into circRNAs: characterization, strategies, and biomedical applications
Strategies for knockdown/overexpression of circRNAs. a Lentivirus carrying shRNA according to the siRNA sequence to make the stable knockdown. sh/siRNA method executes the knockdown based on the complementary base pairing of seed sequences, which has 6–8 bases sponged to BSJ junction site. b CRISPR/Cas13d system degrades circRNAs that requires 28–30 nt long spacers and is intolerant to mismatches in spacers. c CRISPR/Cas9 system knocks out the special circRNA by deleting intronic complementary sequence neighboring the circularized exons. d Overexpression circRNA in a tRNA-derived intronic-circRNA system that followed a fluorescence-based RNA reporter allows to characterize the expression and localization visualization of circRNA. e Conformation of circRNA expression vector containing flanking introns from SUZ12 that splices to express circRNA without extra sequences. f In vitro synthesized RNA circles produced by T4 RNA ligase without extraneous fragments