Coronary angiogenesis was impaired in BAF200 mutant hearts.

<p>(<b>A</b>) Epicardium marker RALDH2 indicates that epicardium integrity remains in E13.5 BAF200 mutants. (<b>B</b>) E12.5 heart explant assays measuring migrating epicardial cells in vitro showed no EMT defect in mutant hearts. White bar = 100 um. (<b>C</b>) Whole mount PECAM staining of E13.0 embryonic hearts. White bar = 0.5 mm. (<b>D</b>) Immunostaining of PECAM on E13.5 embryonic hearts. Dotted blue lines indicate epicardium (Epi). Endo, endocardium; LV, left ventricle; RV, right ventricle. Black bar = 0.2 mm. (<b>E</b>) Immunostaining of AP2 on E13.5 hearts shows vascular endothelial cell (EC) patterning in embryonic hearts. Black bar = 0.2 mm. (<b>F</b>) Quantification of intramyocardial ECs in BAF200 mutant and littermate control hearts. *<i>P</i><0.05; n = 3. (<b>G</b>) Quantitative RT-PCR (qRT-PCR) of vascular endothelial cell marker <i>AP2</i>. *<i>P</i><0.05; n = 8.