FIG. 4.

AHR signaling networks involved in cardiogenesis and cardiac homeostasis. A, The fraction of genes significantly altered in the right atrium of both Ahr^−/− and TCDD-exposed Ahr^+/+ mice (yellow bars) or either solely Ahr^−/− (red bars) or solely TCDD-exposed Ahr^+/+ (blue bars) mice is shown for genes in each of the ontogeny pathways indicated in the abscissa. The green diamonds indicate the percent of genes that are in common between Ahr^−/− and TCDD-exposed Ahr^+/+. Red and blue stars represent the −log(P-value), as a measure of the significance of the observation. B, Same analysis as in (A) for the results with the ventricles. C, Selected list from genes in section (A) of highly concordant genes from Ahr^−/− and ligand-exposed Ahr^+/+ embryo hearts with critical roles in cardiogenesis, and CHD. D, Differentially expressed Ingenuity IPA networks comparison between Ahr^−/− embryo hearts (light blue) and ligand-exposed Ahr^+/+ (dark blue). The vertical red line marks the threshold of statistical significance, as denoted by −log(P-value). Full color version available online.