The mechanisms that govern the identity of renin cells are not well understood. We and others have identified cAMP as an important pathway in the regulation of renin synthesis and release. Recently, experiments in cells from the renin lineage led us to propose that the acquisition and maintenance of renin cell identity is mediated by cAMP and histone acetylation at the cAMP responsive element (CRE) of the renin gene. Ultimately, the transcriptional effects of cAMP depend on the binding of the appropriate transcription factors to CRE. It has been suggested that access of transcription factors to this region of the promoter is facilitated by the coactivators CBP and p300 which possess histone acetyl transferase activity and may be in turn responsible for the remodeling of chromatin underlying expression of the renin gene. We hypothesized that CBP and p300 are therefore required for expression of the renin gene and maintenance of the renin cell. Because mice homozygous for the deletion of either CBP or p300 die before kidney organogenesis starts there are no data on kidney or JG cell development in these mice. Therefore, to define the role of these histone acetyl transferases in renin cell identity in vivo, we used a conditional deletion approach by crossing floxed CBP and p300 mice with mice expressing cre recombinase in renin cells. Results show that the histone acetyl transferases CBP and p300 are necessary for the maintenance of renin cell identity and the structural integrity of the kidney.