Reactome: A Curated Pathway Database

Transfer of GMP from the capping enzyme GT site to 5'-end of mRNA (R-HSA-77083) [Homo sapiens]


The diphosphate 5'-end of the mRNA is joined to the GMP, releasing it from the enzyme. At this time, it is unclear how the RNA diphosphate end is transferred from the active site of the triphosphatase to the guanylyltransferase site. The covalent enzyme-GMP complex can form in the absence of RNA.
Guanylyltransferase (GT) catalyzed second reaction can be represented as:ppN(pN)n + GTP -> GpppN(pN)n + PPi

Additional Information
Compartment nucleoplasm
Components of this entry
Input entries
Output entries
Catalyst Activity
PhysicalEntity Activity Active Units
Capping complex (intermediate) mRNA guanylyltransferase activity (0004484)  
Literature References
pubMedId Title Journal Year
9512541 Isolation and characterization of a human cDNA for mRNA 5'-capping enzyme. Nucleic Acids Res 1998