Scavenger mRNA decapping enzyme DcpS (DcpS)

Scavenger mRNA decapping enzyme DcpS is a member of the histidine triad (HIT) family of hydrolases that plays a key role in eukaryotic mRNA turnover. It hydrolyzes the residual 5' cap structure (m^7^GpppN) from short mRNA fragments produced after 3' to 5' exonucleolytic degradation by the exosome complex, thus preventing the accumulation of cap structures and contributing to overall mRNA decay and gene expression regulation. DcpS acts only on short capped fragments, not on intact mRNA, through a substrate length-sensing mechanism. The enzyme is mainly nuclear, but it shuttles between nucleus and cytoplasm, modulates cap-dependent RNA splicing events via interaction with the cap-binding complex, and defines the HIT motif as a new mRNA decapping domain. DcpS is not to be confused with Dcp2, which acts on full-length mRNA. There are no clinically approved drugs directly targeting DcpS as of the latest reports. No established role as a patient biomarker or specific therapeutic safety concerns in current literature.

Other names

m7GpppX diphosphataseDCPSDecapping scavenger enzymescavenger pyrophosphatase

Hydrolyzes residual 5' cap structures (m^7^GpppN) of short mRNA fragments; Removes cap after 3'->5' exonucleolytic degradation by the exosome complex