title: Viral Epitranscriptomics.
abstract: Although it has been known for over 40 years that eukaryotic mRNAs bear internal base modifications, it is only in the last 5 years that the importance of these modifications has begun to come into focus. The most common mRNA modification, the addition of a methyl group to theN6position of adenosine (m6A), has been shown to affect splicing, translation, and stability, and m6A is also essential for embryonic development in organisms ranging from plants to mice. While all viral transcripts examined so far have been found to be extensively m6A modified, the role, if any, of m6A in regulating viral gene expression and replication was previously unknown. However, recent data generated using HIV-1 as a model system strongly suggest that sites of m6A addition not only are evolutionarily conserved but also enhance virus replication. It is therefore likely that the field of viral epitranscriptomics, which can be defined as the study of functionally relevant posttranscriptional modifications of viral RNA transcripts that do not change the nucleotide sequence of that RNA, is poised for a major expansion in scientific interest and may well fundamentally change our understanding of how viral replication is regulated.
authors.affiliation: Department of Molecular Genetics and Microbiology and Center for Virology, Duke University Medical Center, Durham, North Carolina, USA.
authors.forename: Edward M
authors.initials: EM
authors.lastname: Kennedy
authors.affiliation: Department of Molecular Genetics and Microbiology and Center for Virology, Duke University Medical Center, Durham, North Carolina, USA.
authors.forename: David G
authors.initials: DG
authors.lastname: Courtney
authors.affiliation: Department of Molecular Genetics and Microbiology and Center for Virology, Duke University Medical Center, Durham, North Carolina, USA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Tsai
authors.affiliation: Department of Molecular Genetics and Microbiology and Center for Virology, Duke University Medical Center, Durham, North Carolina, USA bryan.cullen@duke.edu.
authors.forename: Bryan R
authors.initials: BR
authors.lastname: Cullen
mesh_terms: D000241:Adenosine / Q000031:analogs & derivatives* / Q000235:genetics; D004267:DNA Viruses / Q000235:genetics*; D015497:HIV-1 / Q000235:genetics; D006801:Humans; D008745:Methylation; D008780:Methyltransferases / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional / Q000235:genetics*; D012328:RNA Viruses / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*; D012367:RNA, Viral / Q000235:genetics*
chemical_list: D012333:RNA, Messenger; D012367:RNA, Viral; C010223:N-methyladenosine; D008780:Methyltransferases; C468275:METTL3 protein, human; D000241:Adenosine
keywords: HIV-1; N6-methyladenosine; Posttranscriptional gene regulation; RNA modification; mRNA function; mRNA stability