Fig. 2

Short spike of Aldh1a2 expression in neonatal heart. (A, B) RNA-seq-based expression levels of multiple retinoid metabolic genes during murine perinatal heart development (A). The expression levels of Aldh1a2 (orange), Aldh1a3 (green), and Rdh10 (blue) are depicted on the right (B). (n = 2). (C) Quantitative real-time PCR (qRT-PCR) analysis of Aldh1a2 expression in mouse ventricle during heart development. (n = 3; **p < 0.01, One-way ANOVA with Dunnett’s multiple comparisons test relative to eight weeks). (D) Single cell RNA-seq-based Uniform manifold approximation and projection (UMAP) clustering of P2 heart (GSM4644950). Feature Plots of each gene expression showing Aldh1a2 (left panel) and Pdgfra (right panel). (E) Immunofluorescence analysis of ALDH1A2 in mouse heart sections during late-embryonic to neonatal period (green = ALDH1A2, red = PDGFRA, blue = WGA). Note that ALDH1A2 is mainly expressed in cardiac fibroblasts (ALDH1A2⁺PDGFR⁺) and not in cardiomyocytes. Higher magnification images are in the insets. Scale bars, 50 μm. (F) Quantitation of ALDH1A2-positive cells at different developmental stages. (n = 3 mice; **p < 0.01, One-way ANOVA with Dunnett’s multiple comparisons test relative to E18.5). (G) Quantitation of ALDH1A2-positive cells in the subendocardium (red bars), midwall myocardium (yellow bars), and subepicardium (blue bars). All data represents mean ± SEM.