The PGK promoter, as test sequence in a circRNA expression vector context, leads to reporter expression. (A) Schematic diagram of circv1. The positions of the inverted Alu repeats with the two introns are denoted by violet arrowheads. (B) Relative RLuc expression obtained from 293T cells following transfection with circv1 harboring test elements from the indicated genes (Supplemental Table S1). Mock; mock transfection. Values are set relative to those obtained with EMCV Scrb J/K control sequences in circv1. n = 3 ± SEM. (C) Schematic illustrating potential mechanism by which a shortened RLucNTD-containing mRNA produced from the PGK promoter can participate in a trans-splicing reaction to generate a full-length, functional renilla ORF.
