Effect of a regulatory mutation on the rat atrial natriuretic peptide gene transcription.

To investigate the functional relevance of a regulatory mutation affecting the enhancer element PEA2 of the rat ANP gene we transfected rat cardiomyocytes and aortic endothelial cells with either the mutant or the wild-type ANP promoter construct (-683 +54) and performed CAT assays both at baseline and in response to Phenylephrine and Angiotensin II. In the myocardial cells we also determined the DNA/nuclear protein interaction through electrophoretic mobility shift assay. These studies showed a significantly lower degree of ANP transcription in the presence of the mutant PEA2 site, thus demonstrating its functional significance and the biological relevance of ANP gene structural alterations.