Extended Data Fig. 2: Labeling of cardiac cells by Nfatc1-Dre.

a, Schematic figure showing the experimental strategy. b, Immunostaining for WT1 and tdTomato on embryo sections collected from Nfatc1-Dre;R26-RSR-tdTomato mice. The boxed areas are magnified on the right panel with split channels. Arrowheads: white, tdTomato⁺ cells; yellow, WT1⁺ epicardium cells. c, Quantification of the percentage of tdTomato⁺ cells expressing WT1. Data are mean ± s.e.m.; n = 5 mice. d, Schematic figure showing the experimental strategy. e,f, Immunostaining for CD31, PDGFRa, and tdTomato on embryonic sections collected from Nfatc1-Dre;R26-RSR-tdTomato mice. g, Quantification of the percentage of tdTomato⁺ cells expressing PDGFRa or CD31 on the outer layer of hearts collected from Nfatc1-Dre;R26-RSR-tdTomato mice. Data are mean ± s.e.m.; n = 5 mice h, Immunostaining for PDGFRa and GFP on adult heart sections collected from Nfatc1-Dre;Col1a2-CreER;R26-RL-GFP mice. The boxed areas are magnified on the lower panels. i, Quantification of the percentage of PDGFRa⁺ cells expressing GFP of the outer layer of hearts. Data are mean ± s.e.m.; n = 5 mice. Scale bars, yellow, 1 mm, white, 100 µm. Each image is representative of five individual mouse samples.