ADP Ribosylarginine Hydrolase (ADPRH)

The deduced human ADPRH protein has 357 amino acids and an estimated molecular mass of 39.5 kD. Human ADPRH shows 83% amino acid identity to rat Adprh and 82% identity to mouse Adprh. The authors found that the mouse and rat Adprh sequences contain 5 conserved cysteine residues; the human sequence contains only 4 cysteines, with cys108 in rat corresponding to ser103 in human.

Expression of recombinant wildtype and mutant rat and human ADPRH proteins in E. coli and assessment of their DTT requirements for hydrolase activity demonstrated that cys108 is responsible for the DTT dependence of rat Adprh. Northern blot analysis detected a 4.1-kb ADPRH transcript in various human tissues, including fetal and adult brain.