M7GpppX diphosphatase explained

M7GpppX diphosphatase
Ec Number:	3.6.1.59

M7GpppX diphosphatase (DcpS, m7GpppX pyrophosphatase, m7GpppN m7GMP phosphohydrolase) is an enzyme with systematic name m⁷G⁵'ppp5'N m⁷GMP phosphohydrolase.^{[1] [2] [3] [4] [5]} This enzyme catalyses the following chemical reaction

(1) m⁷G⁵'ppp5'N(3'ppp5'N)_n + H₂O

\rightleftharpoons 7-methylguanosine 5'-phosphate + pp5'N(3'ppp5'N)_n

(2) 7-methylguanosine 5'-diphosphate + H₂O

\rightleftharpoons 7-methylguanosine 5'-phosphate + phosphate

Decapping is a process in the control of eukaryotic mRNA degradation.

Notes and References

1. Malys N, McCarthy JE . Dcs2, a novel stress-induced modulator of m7GpppX pyrophosphatase activity that locates to P bodies . Journal of Molecular Biology . 363 . 2 . 370–82 . October 2006 . 16963086 . 10.1016/j.jmb.2006.08.015 .
2. Liu SW, Rajagopal V, Patel SS, Kiledjian M . Mechanistic and kinetic analysis of the DcpS scavenger decapping enzyme . The Journal of Biological Chemistry . 283 . 24 . 16427–36 . June 2008 . 18441014 . 2423256 . 10.1074/jbc.M800341200 . free .
3. Liu H, Rodgers ND, Jiao X, Kiledjian M . The scavenger mRNA decapping enzyme DcpS is a member of the HIT family of pyrophosphatases . The EMBO Journal . 21 . 17 . 4699–708 . September 2002 . 12198172 . 126188 . 10.1093/emboj/cdf448 .
4. van Dijk E, Le Hir H, Séraphin B . DcpS can act in the 5'-3' mRNA decay pathway in addition to the 3'-5' pathway . Proceedings of the National Academy of Sciences of the United States of America . 100 . 21 . 12081–6 . October 2003 . 14523240 . 218716 . 10.1073/pnas.1635192100 . 2003PNAS..10012081V . free .
5. Chen N, Walsh MA, Liu Y, Parker R, Song H . Crystal structures of human DcpS in ligand-free and m7GDP-bound forms suggest a dynamic mechanism for scavenger mRNA decapping . Journal of Molecular Biology . 347 . 4 . 707–18 . April 2005 . 15769464 . 10.1016/j.jmb.2005.01.062 .