Recombinant Hepatitis E virus genotype 1 Non-structural polyprotein pORF1(ORF1),partial

Methyltransferase displays a Cytoplasmic domain capping enzyme activity. This function is necessary since all viral RNAs are synthesized in the cytoplasm, and host capping enzymes are restricted to the nucleus. The enzymatic reaction involves a covalent link between 7-methyl-GMP and the methyltransferase, whereas eukaryotic capping enzymes form a covalent complex only with GMP. Methyltransferase catalyzes transfer of a methyl group from S-adenosylmethionine to GTP and GDP to yield m7GTP or m7GDP. GMP, GpppG, and GpppA were poor substrates for the methyltransferase. This enzyme also displays guanylyltransferase activity to form a covalent complex, methyltransferase-m7GMP, from which 7-methyl-GMP is transferred to the mRNA to create the cap structure. Cap analogs such as m7GTP, m7GDP, et2m7GMP, and m2et7GMP inhibit the methyltransferase reaction .RNA-directed RNA polymerase plays an essential role in the virus replication. Binds to the 3'-end of the genomic RNA, probably to initiate replication ..