Extended Data Fig. 4: Loss of Meis1 and Hoxb13 attenuates both pathological and physiological hypertrophic responses.
From: A calcineurin–Hoxb13 axis regulates growth mode of mammalian cardiomyocytes
a, Schematic representing the TAC model. b, Representative images of M-mode echocardiography (top) and quantification of ejection fraction (bottom), demonstrating improved LVEF in the DKO mice compared with wild-type mice three weeks after TAC. c, Heart weights, showing significantly higher heart weight in the wild-type group. d, Tibia length was similar in both groups. e, f, The ratio of heart weight/body weight (e) and heart weight/tibial length (f) indicate that the DKO mice have a blunted response to pressure overload. g, Representative images of mouse heart sections stained with haematoxylin and eosin (H&E; top) or Masson’s trichrome (bottom) three weeks after surgery. h, Representative confocal images of cardiomyocyte WGA staining (left) and CSA quantification (right), confirming the blunted hypertrophic response in the DKO hearts in response to pressure overload. i, Schematic representation of the exercise protocol. j, Representative images of echocardiography (top) and ejection fraction quantification (bottom), demonstrating no difference in ejection fraction at baseline and after exercise. k, Running distance of control and DKO mice over four weeks, demonstrating no difference between the two groups. l, Heart weight. m, The ratio of heart weight/body weight suggests that both control and DKO hearts respond to exercise-induced cardiac hypertrophy. n, The ratio of heart weight/tibia length also indicates cardiac hypertrophy in both groups in response to exercise. o, Representative images of mouse heart sections stained with either haematoxylin and eosin (top) or Masson’s trichrome (bottom) four weeks after exercise. p, Confocal images of cardiomyocyte WGA staining and CSA quantification. Data are mean ± s.e.m.; unpaired two-sided t-test. Images in g, o are representative of six independently performed experiments with similar results. *P < 0.05, **P < 0.01, ***P < 0.001. For n values, see Methods. Scale bars, 50 μm (h, p), 1 mm (g, o).
