Which are the enzymes involved in the addition of 7-methylguanosine in mRNA?
The 7-methylguanosine cap added to the 5′ end of mRNA is essential for efficient gene expression and cell viability. Methylation of the guanosine cap is necessary for the translation of most cellular mRNAs in all eukaryotic organisms in which it has been investigated. In some experimental systems, cap methylation has also been demonstrated to promote transcription, splicing, polyadenylation and nuclear export of mRNA. In the addition of 7-methylguanosine in mRNA involved the RNA polymerase II, RNA guanylyltransferase and RNA guanine-7 methyltransferase enzymes.