CLONING AND CHARACTERIZATION OF THE MOUSE AND RAT TYPE-II ARGINASE GENES

Two forms of arginase, both catalyzing the hydrolysis of arginine to o rnithine and urea, are found in animals ranging from amphibians to mam mals. In humans, inherited deficiency of hepatic or type I arginase re sults in hyperargininemia, a syndrome characterized by periodic episod es of hyperammonemia, spasticity, and neurological deterioration. In t hese patients, a second extrahepatic or type Ii arginase activity is s ignificantly increased, an induction that may partially compensate for the lack of AI activity and apparently mitigates some of the clinical effects of the condition. Cloning and characterization of the human A II cDNA was recently accomplished. The cloning, sequencing, and partia l characterization of the mouse and rat AII cDNAs are reported herein. The DNA sequences predicted polypeptides of 354 amino acids, includin g a N-terminal mitochondrial import signal. Sequence homology to the h uman type II arginase, arginase activity data, and immunoprecipitation with an anti-AII antibody confirm the identity of these cloned genes as rodent extrahepatic type II arginases. (C) 1998 Academic Press.