Fig. 4

Loss of Mettl14 led to decreased METTL3/WTAP expression and diminished m6A-RNA methylation in RKO retinas. A Reduced expression levels of METTL3 and WTAP in the retinas of 5-month-old RKO mice, as shown by immunoblotting of total lysates of the retinas of Ctrl and RKO mice. B Quantification of relative protein levels in Ctrl and RKO retinas (n = 6). C, D Immunofluorescence labeling of retinal cryosections from Ctrl and RKO mice at the age of 5 months using a METTL3 (C) or WTAP (D) antibody (green). DAPI (blue) was used to counterstain the nuclei. Scale bar: 25 μm. Higher-magnification images of the boxed area are shown in the left panel. Arrowheads indicated that the METTL3/WTAP is still expressed in cone cells. Scale bars: 10 μm. E mRNAs were isolated from retinas, followed by dot blot analysis with an m6A antibody. Methylene blue staining was used as a loading control. F Quantification of the relative m6A levels in E (n = 6). ONL, outer nuclear layer. **p < 0.01; ***p < 0.001. #, no significant difference. Data are presented as the mean ± SEM