( ) deficiency results in cardiac dysfunction, tumorigenesis, inflammation, and decreased survival.

ADP-ribosylation is a reversible reaction with ADP-ribosyltransferases catalyzing the forward reaction and ADP-ribose-acceptor hydrolases (ARHs) hydrolyzing the ADP-ribose acceptor bond. ARH2 is a member of the 39-kDa ARH family (ARH1-3), which is expressed in heart and skeletal muscle. ARH2 failed to exhibit any in vitro enzymatic activity. To determine its possible in vivo activities, -knockout (KO) and - heterozygous (Het) mice were generated using CRISPR-Cas9. -KO mice exhibited decreased cardiac contractility by MRI, echocardiography and dobutamine stress with cardiomegaly and abnormal motor function. -Het mice showed results similar to those seen in -KO mice except for cardiomegaly. -KO and -Het mice and mouse embryonic fibroblasts (MEFs) developed spontaneous tumors and subcutaneous tumors in nude mice. We identified 13 mutations in -Het MEFs and heterozygous tumors, corresponding to human mutations in cancers obtained from COSMIC. Of interest, the L116R mutation in gene plays a critical role in aggressive tumorigenesis in nude mice, corresponding to human mutations in stomach adenocarcinoma. Both genders of -KO and -Het mice showed increased unexpectedly deaths and decreased survival rate during a 24-month observation, caused by tumor, inflammation, non-inflammation (e.g., cardiomegaly, dental dysplasia), and congenital diseases. Thus, plays a pivotal role in cardiac function, tumorigenesis, inflammation, and overall survival.