Fig. 2: Ablation of m6A writers enhanced whereas overexpression of m6A writers reduced H. pylori infection.
a, b Wild type (n = 14 animals) and Mettl3+/− mice (n = 17 animals) were infected with H. pylori strain SS1 for 3 months. a Mouse stomach tissues were harvested and weighted, and then homogenized in sterile PBS. The samples were further diluted and spread on H. pylori-selective blood agar plates. After growing for 5 days, the colony numbers were count for quantitative analysis. b Parafilm-embedded sections of mouse stomach were stained to visualize H. pylori (Red) and the nuclei (Blue). Ten visual fields of each sample were randomly selected to count H. pylori number. Scale bar, 50 μm. c, g Two individual siRNAs or overexpression plasmids were transfected into HFE145 cells to knock down or overexpress METTL3, METTL14 and WTAP, respectively. The knockdown or overexpression efficiency was examined by Western blots. GAPDH served as a loading control. The m6A level of poly(A)+ RNA was examined by Dot blot. Methylene blue (MB) staining was used as a loading control. d–f, h–j HFE145 cells transfected with siRNAs or overexpression plasmids were infected with H. pylori (MOI = 100) for 24 h. d, h Intracellular H. pylori 16S ribosomal DNA levels were measured by real-time PCR. Human GAPDH was used as an internal control (n = 3 replicates for each group). e, i Cells were stained to visualize invaded H. pylori (Red) and the nuclei (Blue). Ten visual fields of each group were randomly selected to count H. pylori number. f, j Cells were permeabilized with 1% saponin for 15 min. The diluted samples were then spread on H. pylori-selective blood agar plates and incubated for 5 days to count the colony number (n = 3 replicates for each group). All the quantitative data were shown as means ± SD. Statistical analysis of the data was performed using unpaired two-tailed Student’s t test (a, b) or one-way ANOVA (d–f, h, i, j) followed by Tukey’s multiple comparison tests with adjustments, and the corresponding p-values are included in the figure panels. The statistical significance of the data (d–f, h, i, j) was calculated from one of three independent experiments with similar results. Source data are provided as a Source Data file.
