ABSTRACT
Classical systemic renin is produced and secreted by modified intrarenal arterial smooth muscle cells in response to appropriate physiological and neurological signals. Cloning of the mouse renin sequences was also instrumental in definitively establishing that gene duplication provided the molecular basis for the high renin salivary phenotype and ultimately, the demonstration that the structural genes for renin, lie coincident with the Rnr locus on chromosome 1. The species-specific duplication of the renin genes in mouse has been the bane as well as the boon of renin research in this organism. The multiplicity of renin genes in this system has complicated analysis of expression and made it incumbent upon investigators to develop methods to distinguish and quantitate gene-specific expression patterns. To identify regulatory DNA sequences, it is necessary to systematically examine the effects of discrete regions with an assay system which can directly measure the effects of linked DNA sequences on expression from a particular promoter.
