Fig. 4. Mettl14 deficiency in Lgr5⁺ stem cells promotes cell apoptosis and DSS-induced colitis.

(A and B) Mettl14^f/f Lgr5^creERT and Mettl14^f/f littermates were treated with tamoxifen daily for 7 days and then sacrificed at day 10 for cleaved caspase-3 staining. Representative cleaved caspase-3 staining of distal colon sections from Mettl14^f/f Lgr5^creERT and Mettl14^f/f mice [(A); scale bars, 70 μm] and quantitative analysis [(B), n = 10 per group]. (C to F) To induce colitis, after treatment with tamoxifen daily for 7 days and resting for 7 days, mice were treated with 2% DSS water for a further 7 days. Weight loss of Mettl14^f/f Lgr5^creERT and Mettl14^f/f mice [(C), n = 8 per group]. Representative photo of colon (D) and colon length measurements from Mettl14^f/f Lgr5^creERT and Mettl14^f/f mice on day 9 [(E), n = 8 per group]. Colonoscopy severity score analysis on day 7 [(F), n = 8 per group]. Data are presented as means ± SD. Two-sided Student’s t test (B) and two-tailed Mann-Whitney U test (C, E, and F) were performed (*P < 0.05; **P < 0.01; ****P < 0.0001).