DBC1 and it homologs from diverse eukaryotes are a catalytically inactive version of the Nudix hydrolase (MutT) domain [1]. DBC1 is predicted to bind NAD metabolites and regulate the activity of SIRT1 or related deacetylases by sensing the soluble products or substrates of the NAD-dependent deacetylation reaction [1].

1: Analysis of DBC1 and its homologs suggests a potential mechanism for regulation of sirtuin domain deacetylases by NAD metabolites. Anantharaman V, Aravind L; Cell Cycle. 2008;7:1467-1472. PMID:18418069