DCPS

This gene encodes a member of the histidine triad family of pyrophosphatases that removes short mRNA fragments containing the 5′ mRNA cap structure, which appear in the 3′ → 5′ mRNA decay pathway, following deadenylation and exosome-mediated turnover. This enzyme hydrolyzes the triphosphate linkage of the cap structure (7-methylguanosine nucleoside triphosphate) to yield 7-methylguanosine monophosphate and nucleoside diphosphate. It protects the cell from the potentially toxic accumulation of these short, capped mRNA fragments, and regulates the activity of other cap-binding proteins, which are inhibited by their accumulation. It also acts as a transcript-specific modulator of pre-mRNA splicing and microRNA turnover.

Full Name

decapping enzyme, scavenger

Function

Decapping scavenger enzyme that catalyzes the cleavage of a residual cap structure following the degradation of mRNAs by the 3'->5' exosome-mediated mRNA decay pathway. Hydrolyzes cap analog structures like 7-methylguanosine nucleoside triphosphate (m7GpppG) with up to 10 nucleotide substrates (small capped oligoribonucleotides) and specifically releases 5'-phosphorylated RNA fragments and 7-methylguanosine monophosphate (m7GMP). Cleaves cap analog structures like tri-methyl guanosine nucleoside triphosphate (m3(2,2,7)GpppG) with very poor efficiency. Does not hydrolyze unmethylated cap analog (GpppG) and shows no decapping activity on intact m7GpppG-capped mRNA molecules longer than 25 nucleotides. Does not hydrolyze 7-methylguanosine diphosphate (m7GDP) to m7GMP (PubMed:22985415).

May also play a role in the 5'->3 mRNA decay pathway; m7GDP, the downstream product released by the 5'->3' mRNA mediated decapping activity, may be also converted by DCPS to m7GMP (PubMed:14523240).

Binds to m7GpppG and strongly to m7GDP. Plays a role in first intron splicing of pre-mRNAs. Inhibits activation-induced cell death.

Biological Process

Cellular response to menadione Source: UniProtKB
Deadenylation-dependent decapping of nuclear-transcribed mRNA Source: GO_Central
Exonucleolytic catabolism of deadenylated mRNA Source: Reactome
mRNA cis splicing, via spliceosome Source: UniProtKB
Negative regulation of programmed cell death Source: UniProtKB
Nuclear-transcribed mRNA catabolic process, deadenylation-dependent decay Source: UniProtKB

Cellular Location

Cytoplasm; Nucleus. Predominantly localized in the nucleus. Nucleocytoplasmic shuttling protein that can transiently enter the cytoplasm in mammalian cells in a XPO1/CRM1-dependent manner.

Involvement in disease

Al-Raqad syndrome (ARS):
A syndrome characterized by delayed psychomotor development, moderate to severe intellectual disability, poor or absent speech, microcephaly, congenital hypotonia, and severe growth delay.