DCPS, also known as scavenger mRNA-decapping enzyme, is belongs to the HIT family. It is necessary for the complete degradation of mRNAs, both in normal mRNA turnover and in nonsense-mediated mRNA decay. A scavenger decapping enzyme, DcpS was shown to hydrolyze the residual m7GpppN cap structure after the complete 3′–5′ degradation of the mRNA by the exosome.