ARH3 (E8A6G) Rabbit mAb #32205

ADP-ribosylation is a reversible post-translational modification (PTM) where a single unit or polymers of ADP-ribose (ADPr) groups from β-nicotinamide adenine dinucleotide (NAD⁺) are transferred onto specific residues of target proteins (1). In addition to proteins, DNA and RNA molecules have also been identified as targets of ADP-ribosylation (2,3). This modification is catalyzed by a diverse group of ADP-ribosyltransferases (ARTs), with the majority of them functioning to add a single ADPr unit (MARylation) while the deposition of multiple ADPrs are done by poly (ADP-ribose) polymerases (PARPs). Reversal of ADP-ribosylation is accomplished by the evolutionarily distinct macrodomain and ADP-ribosylhydrolase (ARH) protein families (4). Specifically, poly (ADP-ribose) glycohydrolase (PARG) or ADP-ribosylhydrolase 3 (ARH3) degrade PARylation down to single ADPr units and MacroD1, MacroD2, TARG1, or ARH1 fully remove them from target residues (5). ADP-ribosylation and the enzymes that regulate it are involved in a wide range of cellular processes, such as DNA repair, chromatin regulation, transcription, and cellular stress response (1,4). Moreover, ADP-ribosylation has been shown to be a therapeutically critical PTM in various cancers, neurodegenerative diseases, and inflammation (6).

The ARH family of ADP-ribose hydrolases contains three proteins with similarities in amino acid sequence but differences in their enzymatic activities. ARH3, also known as ADPRHL2, is a ubiquitous protein that localizes to the nucleus, cytosol, and mitochondria in a cell-type specific manner (7-9). ARH3 exhibits partial redundancy with PARG in their preference for hydrolysis of DNA damage-induced serine ADP-ribosylation which underlies a key role for these enzymes in maintaining genomic stability. Arh3-KO mice have been shown to develop increased brain infarction in response to ischemia-reperfusion injury (10) and human ARH3-deficiency is a rare recessive autosomal disorder characterized by neurodegeneration and early death (11,12).