Fig. 12

Inhibition of autophagy leads to cardiac malformation in the absence of Hspb7. Shown are representative images of 72 hpf, bafilomycin A (BafA)-treated wildtype (A) or hspb7^WC3/WC3 mutant (B) embryos with a tg(myl7: gfp) background showing a cardiac malformation with expansion of the atrium and an undersized ventricle in the hspb7^WC3/WC3 fish. (C) Quantification of the percentage of embryos with cardiac abnormalities at 48 hpf, following 24 h treatment with increasing concentrations of Bafilomycin A. n = 40 for each treatment group. (D) hspb7 mutant embryos consistently exhibit significant increases in cardiac abnormalities following treatment with Bafilomycin A. (E) Quantification of cardiac abnormalities in embryos treated with proteasome inhibitor MG132 does not lead to increases in abnormalities in cardiac development in hspb7 mutants. (F) Autophagy inhibitor chloroquine diphosphate (CQ) leads to increases in abnormalities in cardiac development in hspb7 mutants at a greater rate than is seen in wildtype embryos. (G) Treating larvae with the autophagy inhibitor 3-Methyladenine (3-MA) leads to increases in abnormalities in cardiac development in hspb7 morphants at a rate greater than is seen in wildtype control embryos. Abnormalities included small ventricles, unlooped hearts and atrial ballooning. For C, D, F, and G, changes in cardiac abnormalities are significant according to an unpaired t-test, corrected for multiple comparisons with the Holm-Sidak method.