Author(s): Canales, José ; Fernández, Ascensión ; Rodrigues, Joaquim Rui ; Ferreira, Rui ; Ribeiro, João Meireles ; Cabezas, Alicia ; Costas, María Jesús ; Cameselle, José Carlos
Date: 2009
Persistent ID: http://hdl.handle.net/10400.8/3028
Origin: IC-online
Subject(s): Adenosine Diphosphate Ribose; Animals; Cyclic ADP-Ribose; Hydrolysis; Manganese; Models, Molecular; Pyrophosphatases; Rats; Substrate Specificity
Cyclic ADP-ribose (cADPR) metabolism in mammals is catalyzed by NAD glycohydrolases (NADases) that, besides forming ADP-ribose, form and hydrolyze the N(1)-glycosidic linkage of cADPR. Thus far, no cADPR phosphohydrolase was known. We tested rat ADP-ribose/CDP-alcohol pyrophosphatase (ADPRibase-Mn) and found that cADPR is an ADPRibase-Mn ligand and substrate. ADPRibase-Mn activity on cADPR was 65-fold less efficient than on ADP-ribose, the best substrate. This is similar to the ADP-ribose/cADPR formation ratio by NADases. The product of cADPR phosphohydrolysis by ADPRibase-Mn was N(1)-(5-phosphoribosyl)-AMP, suggesting a novel route for cADPR turnover.
