Decapping and exoribonuclease protein (DXO)

Decapping and exoribonuclease protein (DXO) is a multifunctional enzyme critically involved in the surveillance and processing of messenger RNA (mRNA) within eukaryotic cells. DXO exhibits multiple biochemical activities, acting as a decapping enzyme, pyrophosphohydrolase, and 5'-3' exoribonuclease[1][2]. It specifically targets and removes incomplete or defective 5′ cap structures from pre-mRNA and nascent transcripts, thereby promoting the degradation of aberrant mRNAs by exonucleolytic digestion[2]. This protein ensures the fidelity of gene expression by eliminating transcripts that fail to receive a fully mature 7-methylguanosine cap or are capped with alternative groups such as NAD+, thereby preventing the accumulation of faulty pre-mRNAs and maintaining proper mRNA processing and turnover[1][2]. DXO function is essential for mRNA quality control, but remains largely unaffected by mature, properly capped mRNA, which are protected by cap-binding proteins. The enzyme is conserved from yeast to mammals (often named Dom3Z/Rai1 in other species) and plays an emerging role in gene expression regulation and post-transcriptional control mechanisms[2]. No evidence exists of currently approved drugs targeting DXO directly, nor has it established use as a biomarker or specific safety concerns described in the available literature[1][2]. However, DXO function is linked to cancer proliferation pathways, indicating potential future relevance in disease modulation[1].

Other names

DOM3LDOM3ZNG6RAI1DeNADding enzyme DXOprotein Dom3Z5'-3' exoribonuclease DXONAD-capped RNA hydrolase DXO