RBM3-mediated m6A modification of KLF6 promotes ACSL4-driven ferroptosis in ulcerative colitis.

Abstract

This study aimed to explore how RBM3-mediated m6A modification enhances the stability of KLF6 mRNA and promotes ferroptosis via ACSL4 activation in a mouse model of ulcerative colitis (UC). UC mouse model was induced by dextran sulfate sodium salt (DSS). Meanwhile, primary colonic epithelial cells were exposed to DSS in vitro to construct a cellular model of UC. Pathological changes in colonic tissues were assessed by H&E staining. Inflammatory cytokine levels were assayed using enzyme-linked immunosorbent assay (ELISA). Protein expression of ZO-1, Occludin, RBM3, KLF6, and ACSL4 in colonic tissues was detected by immunohistochemistry. Ferroptosis-related indicators were quantified using kits. Cell viability was assessed by CCK-8 assay, and RBM3, KLF6, and ACSL4 expression levels were determined by RT-qPCR and western blot. Bioinformatics tools predicted m6A sites in KLF6 mRNA. RIP assays validated RBM3-KLF6 mRNA binding. m6A modification of KLF6 mRNA was detected by MeRIP-qPCR. KLF6 mRNA stability was evaluated by actinomycin D assay, and the KLF6 mRNA half-life was analyzed. RBM3 was upregulated in the UC mouse model. RBM3 knockdown can reduce ferroptosis and attenuate histological damage in UC mice. Mechanistically, RBM3 stabilized KLF6 mRNA expression through m6A modification, thereby promoting KLF6-mediated ACSL4 transcription and ferroptosis. Knockdown of RBM3 or KLF6 inhibits ferroptosis, while KLF6/ACSL4 overexpression can partially reverse the regulatory effect of RBM3 knockdown on ferroptosis. RBM3 promotes UC progression by enhancing m6A-mediated KLF6 stability and activating ACSL4-driven ferroptosis, suggesting RBM3 and KLF6 as potential therapeutic targets.