Fig. 3

Wwtr1 functions cell-autonomously in cardiomyocytes to regulate tp1 Notch reporter expression. (A) Confocal sagittal sections of representative ventricular chambers at 72 and 96 hpf. Yellow arrows indicate cardiomyocytes expressing the tp1 Notch reporter. The out of focus green signal is from endocardial cells at the valve regions (asterisks). Scale bars: 15 μm. (B) Number of tp1⁺ ventricular cardiomyocytes at 96 hpf. Each point represents a heart. ***P<0.001 by Poisson regression. (C,D) Maximum intensity projections of hearts derived from transplanting wild-type cells into wwtr1^+/− or wwtr1^−/− hosts (C), and vice versa (D). Scale bars: 10 μm. (C′,D′) Number of tp1⁺ donor and host cardiomyocytes (CMs) according to the respective transplantation schemes, as indicated on the x-axis. Each point represents a heart. P-values were calculated using an exact Binomial test. The box covers the inter-quartile range (IQR); the whiskers cover the first and last quartile of the data. Data points outside the whiskers are outliers (>1.5×IQR from the first and third quartile).