Arginase catalyzes the conversion of L-arginine to L-ornithine and urea in the livers of ureotelic organisms. The hepatic arginase f AI) is immunologically and physico-chemically distinct from a second extrahepatic form of arginase (All) found in many tissues including brain, kidney, small intestine, mammary gland and macrophages. All is encoded at one or more discrete loci and is involved in nitric oxide regulation, immune function, polyamine metabolism and proline/glutainate synthesis. The present study seeks to isolate and characterize All preparatory to further'investigations of itUs various physiological roles. Comparison of human Expressed Sequence Tags (ESTs) with postulated extrahepatic arginase sequences from Xenopus leavis enabled the derived consensus sequences to be utilized for PCR-based amplification of a full-lenth putative human All cDNA sequence. The identity of this clone as an authentic All sequence was confirmed by evolutionary sequence analysis, enzyme activity of the expressed clone, and immunoprecipitation studies. The All sequence was used to determine tissue expression and species distribution by nucleic acid hybridization. This represents the first isolation and identification of a novel human arginase gene of extrahepatic origin and presents a unique opportunity for elucidation of it's role in essential metabolic pathways.
|Original language||English (US)|
|State||Published - Dec 1 1996|
ASJC Scopus subject areas
- Molecular Biology