Catalysis of the reaction: a 5'-end NAD+-phospho-ribonucleoside in mRNA + H2O = a 5'-end phospho-adenosine-phospho-ribonucleoside in mRNA + beta-nicotinamide D-ribonucleotide + 2 H+.
Source:
GOC:sp,
PMID:31101919,
RHEA:60876,
PMID:25533955
Comment
This reaction specifically removes the nicotinamide adenine dinucleotide (NAD) cap from a subset of mRNAs by hydrolyzing the diphosphate linkage to produce nicotinamide mononucleotide (NMN) and 5' monophosphate mRNA.