The role of the Grb2–p38 MAPK signaling pathway in cardiac hypertrophy and fibrosis
J. Clin. Invest. Shaosong Zhang, et al. 111:833 doi:10.1172/JCI16290 [Go to this article.]

Figure 5
Biochemical characterization of DN-p38α and DN-p38β transgenic mice. (a) Analysis of DN-p38α and DN-p38β MAPK protein levels in cardiac tissue from transgenic mice. Ventricular protein lysates obtained from DN-p38α mice, DN-p38β mice, and nontransgenic Swiss Black mice were separated by SDS-PAGE and examined by immunoblotting. Upper panel, isoform-specific anti–p38α MAPK immunoblot. Middle panel, isoform-specific anti–p38β MAPK immunoblot. Lower panel, anti-ERK immunoblot to control for protein loading. (b) Reduced p38α MAPK activity in DN-p38α transgenic mice. Ventricular protein lysates were generated 7 days after TAC or sham operation in DN-p38α transgenic mice or nontransgenic Swiss Black mice (NTG). Upper panel, anti-phospho–p38 MAPK immunoprecipitates were analyzed by isoform-specific anti–p38α MAPK immunoblotting. Middle panel, ventricular lysates were analyzed by anti-ERK immunoblotting to control for protein content. Lower panel, quantification of p38α MAPK protein levels in ventricular lysates by densitometric analysis of immunoreactive bands. Data are from three experiments. (c) Reduced p38β MAPK activity in DN-p38β transgenic mice. Upper panel, anti-phospho–p38 MAPK immunoprecipitates were analyzed by isoform-specific anti–p38β MAPK immunoblotting. Middle panel, ventricular lysates were analyzed by anti-ERK immunoblotting to control for protein content. Lower panel, quantification of p38β MAPK protein levels by densitometric analysis of immunoreactive bands. Data are from three experiments.