Fig. 5
Effects of Cdk9 modulation on ventricle cardiomyocyte proliferation during early development of the zebrafish heart. Effects of flavopiridol (A, white bars, controls; black bars, flavopiridol 3µmol/l) on the total number of cardiomyocytes in the isolated embryonic zebrafish ventricle. Effects of Cdk9 morpholino (B, Cdk9-Mo-SB, Cdk-Mo) and Larp7 morpholino (C, Larp7-Mo-SB, Larp7-Mo) on total cardiomyocyte number in the embryonic ventricle (white bars, controls, appropriate mismatch morpholino; dark bars, splice-blocking morpholino. Effects of flavopiridol on the number of proliferating cardiomyocytes (D, white bars, controls; black bars, flavopiridol 3µmol/l). Representative confocal images (E) of isolated embryonic myl7:GFP hearts stained with DAPI (blue) and for phospho-Histone-H3 (PHH3, red nuclei, marking proliferating cardiomyocytes). Data are mean±s.e.m., n=3 experiments, n=5 hearts per group, *P<0.05, **P<0.01 ***P<0.001, two-way ANOVA test. Means±s.e.m. are shown in A, B, C and D.