One viral epitranscriptome modification that has been identified is the 5-methylcytidine (mC). HIV-1 and MLV transcriptomes contain elevated levels of these residues by approximately 14-30 fold when compared to a cell’s normal levels. NSUN2 is the complex that codes the cytidine methyltransferases credited with mC formation in cells and amplification in viral epitranscriptomes. The NSUN2 affects the translational aspect of the mRNA in the viral cells, boosting the expression of the viral genome. It has also been found that the mC alters the splicing pattern and locations in the viral transcriptome. This affected the HIV-1 transcript in both early and late infection.