Table 1.
List of RNA modifications and functions associated with RNA viruses
| RNA virus | Function | References |
|---|---|---|
| N7‐methylguanosine (m7G) | ||
| Viruses within Corona‐, Arteri‐, Rhabdo‐, Filo‐, Paramyxo‐, Pox‐, and Reo‐, Retro‐, Togaviridae families and flavivirus genus | • m7G in 5′‐cap promotes translation and RNA stability | Decroly and Canard (2017), Decroly et al. (2012) |
| Zika virus, Dengue virus, HCV, Poliovirus, HIV‐1 and Murine leukemia virus | • To be determined for m7G modifications within genome | Courtney et al. (2019), McIntyre et al. (2018) |
| 2′‐O‐methylated nucleotides (Nm) | ||
| Viruses within Corona‐, Arteri‐, Rhabdo‐, Filo‐, Paramyxo‐, Pox‐, and Reoviridae families and flavivirus genus | • Nm at 5′‐end: Escape innate immune sensing | Hyde and Diamond (2015) |
| HIV‐1 | • Internal Nm: Escape innate immune sensing | McIntyre et al. (2018), Ringeard, Marchand, Decroly, Motorin, and Bennasser (2019) |
| Dengue virus | • Internal Am restricts elongation of viral RNA‐dependent RNA polymerase | Dong et al. (2012) |
| Pseudouridine (Ψ) | ||
| Turnip yellow mosaic virus and Brome mosaic virus | • Possibly promotes RNA structure | Baumstark and Ahlquist (2001), Becker (1998) |
| Tobacco mosaic virus | • Ψ within tRNATyr anticodon loop terminates translation of viral polymerase | Zerfass and Beier (1992) |
| Zika virus, Dengue virus, HCV, Poliovirus, and HIV‐1 | • To be determined | McIntyre et al. (2018) |
| Inosine (I) | ||
| Measles virus and Respiratory syncytial virus |
• Introduces a mutation and affects mRNA coding capacity • Causes frameshift which terminates synthesis of viral proteins • Suppresses innate immune response |
Cattaneo et al. (1988), Martínez, Dopazo, and Melero (1997), Pfaller, Donohue, Nersisyan, Brodsky, and Cattaneo (2018), Rueda, García‐Barreno, and Melero (1994) |
| Hepatitis δ virus | • Maintains balance between replication and virus production | Casey (2006) |
| HIV‐1 | • Introduces a mutation and affects codon and splicing of viral RNA | Doria, Neri, Gallo, Farace, and Michienzi (2009), McIntyre et al. (2018), Phuphuakrat et al. (2008) |
| HCV | • Affects viral gene expression | Taylor, Puig, Darnell, Mihalik, and Feinstone (2005) |
| Zika virus, Dengue virus, and Poliovirus | • To be determined | Khrustalev, Khrustaleva, Sharma, and Giri (2017), McIntyre et al. (2018), Piontkivska, Frederick, Miyamoto, and Wayne (2017) |
| N6‐methyladenosine (m6A) | ||
| HIV‐1 |
• Modulates HIV‐1 gene expression early and late in infection • Affects stability of viral RNA • Influences export of HIV‐1 RNA out of nucleus |
Kennedy et al. (2016), Lichinchi, Gao, et al. (2016), Lu et al. (2018), Tirumuru and Wu (2019), Tirumuru et al. (2016) |
| Avian sarcoma virus and Rous sarcoma virus | • Affects splicing of viral RNA | Beemon and Keith (1977), Dimock and Stoltzfus (1977), Kane and Beemon (1985), Stoltzfus and Dane (1982) |
| Murine leukemia virus | • Affects viral gene expression | Courtney et al. (2019) |
| Influenza virus |
• Promotes infection kinetics • Decreases virus pathogenicity |
Courtney et al. (2017), Krug, Morgan, and Shatkin (1976), Narayan, Ayers, Rottman, Maroney, and Nilsen (1987) |
| HCV | • Negatively regulates the production of new virus particles | Gokhale et al. (2016) |
| Zika virus, Dengue virus, West Nile virus, Yellow fever virus, Poliovirus, and Enterovirus 71 | • Affects viral gene expression | Gokhale et al. (2016), Hao et al. (2019), Lichinchi, Zhao, et al. (2016), McIntyre et al. (2018) |
| 5‐Methylcytosine (m5C) | ||
| Sindbis virus and Drosophila C virus | • m5C methyltransferase (Mt or Dnmt) modulates innate immune responses | Bhattacharya, Newton, and Hardy (2017), Dubin and Stollar (1975), Dubin, Stollar, Hsuchen, Timko, and Guild (1977), Durdevic et al. (2013) |
| Murine leukemia virus | • Affects viral gene expression and infectivity | Courtney et al. (2019) |
| Zika virus, Dengue virus, HCV, Poliovirus, and HIV‐1 | • To be determined | McIntyre et al. (2018) |
Abbreviations: HCV, hepatitis C virus; HIV‐1, human immunodeficiency virus 1.