Homologous Superfamily

Scavenger mRNA decapping enzyme, N-terminal (IPR011145)

Short name: Scavenger_mRNA_decap_enz_N

Overlapping entries


This superfamily represents the N-terminal domain of scavenger mRNA decapping enzymes, such as Dcp2 and DcpS. DcpS is a scavenger pyrophosphatase that hydrolyses the residual cap structure following 3' to 5' mRNA degradation. DcpS uses cap dinucleotides or capped oligonucleotides as substrate to release m(7)GMP (N7-methyl GMP), while Dcp2 uses capped mRNA as substrate in order to hydrolyse the cap to release m(7)GDP (N7-methyl GDP) [PMID: 16246173]. The association of DcpS with 3' to 5' exonuclease exosome components suggests that these two activities are linked and there is a coupled exonucleolytic decay-dependent decapping pathway. The superfamily contains a histidine triad (HIT) sequence with three histidines separated by hydrophobic residues [PMID: 16001405]. The central histidine within the DcpS HIT motif is critical for decapping activity and defines the HIT motif as a new mRNA decapping domain, making DcpS the first member of the HIT family of proteins with a defined biological function.

GO terms

Biological Process

GO:0000290 deadenylation-dependent decapping of nuclear-transcribed mRNA

Molecular Function

GO:0016787 hydrolase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.