Although the SH3 domain containing ring finger 2 protein (SH3RF2) has been identified as a marker of the nucleus accumbens in the human brain, little is known about this protein. Recent yeast two-hybrid experiments have shown that SH3RF2 associates with protein phosphatase 1 (PP1) and is expressed primarily in heart and testis tissue. Recombinant SH3RF2 enhanced PP1 enzymatic activity and antagonized the ability of phopho-inhibitor-1 or -2 to inhibit PP1, suggesting that SH3RF2 may play a role working with PP1 in cardiac functions.Synonyms: Putative E3 ubiquitin-protein ligase SH3RF2, RING finger protein 158, SH3 domain-containing RING finger protein 2