Decapping Enzyme 1A (DCP1A)

DCP1A and another decapping enzyme form a decapping complex, which interacts with the nonsense-mediated decay factor hUpf1 and may be recruited to mRNAs containing premature termination codons. This protein also participates in the TGF-beta signaling pathway.Recombinant DCP1A fused to an N-terminal GST tag was inactive in decapping activity, but FLAG-tagged DCP1A expressed in human embryonic kidney cells was active. Mutation of asn20 and arg59 reduced DCP1A decapping activity by 4- and 12-fold, respectively, and both mutations resulted in reduced protein stability. Coimmunoprecipitation assays demonstrated that DCP1A and DCP2 interacted with the nonsense-mediated decay factor UPF1 (RENT1) both in the presence and in the absence of other UPF proteins.