Renin mRNA isolated from mouse submaxillary gland as found to direct the synthesis of renin protein as determined by in vitro and in vivo translation analyses using rabbit reticulocyte lysate and Xenopus laevis oocytes. Renin cDNA was then synthesized from the renin mRNA by the reverse transcription and polymerase chain reaction and inserted into HindIII site of pUC19. E. coli JM103 transformed with the recombinant plasmid, referred to as pUCR, effidiently accumulated the renin protein (Mr=45,000). Furthermore, the renin purified from the transformant effectively induced hypertension when injected to rabbit. These results indicate that the cDNA synthesized from the putative renin mRNA is in correct reading frame and directs the production of biologically active form of renin