Fig. 3: Histological and molecular characterization of Clk4-cKO mice.

a H&E-stained heart sections from MCM control and Clk4-cKO hearts. Scale bar: 1 mm. b, c Summary data for LV internal diameter (LVID) and interventricular septum (IVS) thickness. d, e WGA staining and quantification of cardiomyocyte cross-sectional area. Scale bar: 50 μm. f, g WGA staining, and quantification of cardiomyocyte length. Scale bar: 25 μm. h, i Masson’s trichrome staining of heart sections and quantification of myocardial fibrosis. Scale bar: 50 μm. j Transmission electron micrographs comparing control and Clk4-cKO hearts. Mt mitochondrion, Mf myofibril, LD lipid droplet, red asterisk, mitochondria; red arrow, blurred and widened Z-disks; black arrow, ruptured myofibril. Scale bars: 500 nm. k qPCR analysis of cardiac hypertrophic genes, including Nppa, Nppb and Myh7. For b, c, e, g, i and k, n = 5 animals per group. All statistical analyses were performed using unpaired, two-tailed Student’s t test. Data are presented as the means ± S.E.M.; P values are shown in each graph. Source data are provided as a Source Data file.