The process of messenger RNA decapping consists of hydrolysis of the 5' cap structure on the RNA exposing a 5' monophosphate. In eukaryotes, this 5' monophosphate is a substrate for the 5' exonuclease Xrn1[1] and the mRNA is quickly destroyed. There are many situations which may lead to the removal of the cap, some of which are discussed below.[2]
In prokaryotes, the initial mRNA transcript naturally possesses a 5'-triphosphate group after bacterial transcription; the enzyme RppH removes a pyrophosphate molecule from the 5' end, converting the 5'-triphosphate to a 5'-monophosphate, triggering mRNA degradation by ribonucleases.[3][4]
- ^ Poole, Toni L.; Stevens, Audrey (June 1997). "Structural Modifications of RNA Influence the 5′ Exoribonucleolytic Hydrolysis by XRN1 and HKE1 ofSaccharomyces cerevisiae". Biochemical and Biophysical Research Communications. 235 (3): 799–805. doi:10.1006/bbrc.1997.6877. PMID 9207242.
- ^ Meyer, Sylke; Temme, Claudia; Wahle, Elmar (January 2004). "Messenger RNA Turnover in Eukaryotes: Pathways and Enzymes". Critical Reviews in Biochemistry and Molecular Biology. 39 (4): 197–216. doi:10.1080/10409230490513991. PMID 15596551. S2CID 21227254.
- ^ Deana, Atilio; Celesnik, Helena; Belasco, Joel G. (17 January 2008). "The bacterial enzyme RppH triggers messenger RNA degradation by 5′ pyrophosphate removal". Nature. 451 (7176): 355–358. Bibcode:2008Natur.451..355D. doi:10.1038/nature06475. PMID 18202662. S2CID 4321451.
- ^ Hsieh, Ping-kun; Richards, Jamie; Liu, Quansheng; Belasco, Joel G. (22 April 2013). "Specificity of RppH-dependent RNA degradation in Bacillus subtilis". Proceedings of the National Academy of Sciences. 110 (22): 8864–8869. Bibcode:2013PNAS..110.8864H. doi:10.1073/pnas.1222670110. PMC 3670361. PMID 23610425.