Image
Figure Caption

Fig. 5

Epicardial shha expression promotes subepicardial cardiomyocyte proliferation during heart regeneration.

(A) Schematic of the experiment. (B) Semi-qRT-PCR analysis of shha in purified tcf21:DsRed2+ epicardial cells obtained from uninjured and injured (7 dpi) tcf21:DsRed hearts. Injury was confirmed by the induction of raldh2 expression. (C) Semi-qRT-PCR analysis of Hh pathway genes using purified tcf21:DsRed2+ epicardial cells obtained from 4-HT–treated 7 dpi tcf21:DsRed; shhact/ct (control, left) and tcf21:DsRed; tcf21:CreER; shhact/ct hearts (right). (D) Immunofluorescence images of the subepicardial (top) and trabecular areas (bottom) of heart sections obtained from 4-HT–treated 7 dpi shhact/ct (control) or tcf21:CreER; shhact/ct hearts. Brackets, subepicardial areas. Dotted lines, approximate amputation plane. Arrows indicate proliferating cardiomyocytes. (E) Quantification of cardiomyocyte proliferation in the subepicardial and trabecular areas of the heart sections obtained from 4-HT–treated 7 dpi shhact/ct (control) or tcf21:CreER; shhact/ct hearts shown in D (n = 6 each). The data are presented as the mean ± SEM (**p<0.01, Mann–Whitney U test). N.S., not significant (p=0.3367). (F) Image of heart sections obtained from 7 dpi gata4:EGFP; tcf21;DsRed2 fish. Subepicardial cardiomyocytes (green, arrows) associate with epicardial cells (magenta, arrowheads). (G) Semi-qRT-PCR analysis of shha pathway genes using purified subepicardial cardiomyocytes obtained from 7 dpi gata4:EGFP ventricles. Cardiomyocytes purified from uninjured cmlc2:EGFP ventricles were used as negative controls. Scale bar, 50 μm.

Figure Data
Acknowledgments
This image is the copyrighted work of the attributed author or publisher, and ZFIN has permission only to display this image to its users. Additional permissions should be obtained from the applicable author or publisher of the image. Full text @ Elife