- Chantal B.F. Vogels (1)
- Sjef Boeren (1)
- Anwar Hiralal (1)
- Jelke J. Fros (2)
- Constantianus J.M. Koenraadt (1)
- Bas M. Fernhout (1)
- Monique M. Oers van (1)
- Tessa M. Visser (1)
- Giel P. Göertz (2)
- Gorben P. Pijlman (2)
- Sandra R. Abbo (2)
- Carmen Steffens (1)
- Joyce W.M. Bree van (1)
Subgenomic flavivirus RNA binds the mosquito DEAD/H-box helicase ME31B and determines Zika virus transmission by Aedes aegypti
Göertz, Giel P. ; Bree, Joyce W.M. van; Hiralal, Anwar ; Fernhout, Bas M. ; Steffens, Carmen ; Boeren, Sjef ; Visser, Tessa M. ; Vogels, Chantal B.F. ; Abbo, Sandra R. ; Fros, Jelke J. ; Koenraadt, Constantianus J.M. ; Oers, Monique M. van; Pijlman, Gorben P. - \ 2019
Proceedings of the National Academy of Sciences of the United States of America 116 (2019)38. - ISSN 0027-8424 - p. 19136 - 19144.
Aedes aegypti - Purification - RNA-affinity - Subgenomic flavivirus RNA - Transmission - Zika virus
Zika virus (ZIKV) is an arthropod-borne flavivirus predominantly transmitted by Aedes aegypti mosquitoes and poses a global human health threat. All flaviviruses, including those that exclusively replicate in mosquitoes, produce a highly abundant, noncoding subgenomic flavivirus RNA (sfRNA) in infected cells, which implies an important function of sfRNA during mosquito infection. Currently, the role of sfRNA in flavivirus transmission by mosquitoes is not well understood. Here, we demonstrate that an sfRNA-deficient ZIKV (ZIKVΔSF1) replicates similar to wild-type ZIKV in mosquito cell culture but is severely attenuated in transmission by Ae. aegypti after an infectious blood meal, with 5% saliva-positive mosquitoes for ZIKVΔSF1 vs. 31% for ZIKV. Furthermore, viral titers in the mosquito saliva were lower for ZIKVΔSF1 as compared to ZIKV. Comparison of mosquito infection via infectious blood meals and intrathoracic injections showed that sfRNA is important for ZIKV to overcome the mosquito midgut barrier and to promote virus accumulation in the saliva. Next-generation sequencing of infected mosquitoes showed that viral small-interfering RNAs were elevated upon ZIKVΔSF1 as compared to ZIKV infection. RNA-affinity purification followed by mass spectrometry analysis uncovered that sfRNA specifically interacts with a specific set of Ae. aegypti proteins that are normally associated with RNA turnover and protein translation. The DEAD/H-box helicase ME31B showed the highest affinity for sfRNA and displayed antiviral activity against ZIKV in Ae. aegypti cells. Based on these results, we present a mechanistic model in which sfRNA sequesters ME31B to promote flavivirus replication and virion production to facilitate transmission by mosquitoes.
Functional RNA during Zika virus infection
Göertz, Giel P. ; Abbo, Sandra R. ; Fros, Jelke J. ; Pijlman, Gorben P. - \ 2018
Virus Research 254 (2018). - ISSN 0168-1702 - p. 41 - 53.
5' and 3' untranslated regions - Codon usage bias - Dinucleotides - G-quadruplex - Nucleotide composition - RNA methylation - Subgenomic flavivirus RNA - Virus-host interactions - Zika virus
Zika virus (ZIKV; family Flaviviridae; genus Flavivirus) is a pathogenic mosquito-borne RNA virus that currently threatens human health in the Americas, large parts of Asia and occasionally elsewhere in the world. ZIKV infection is often asymptomatic but can cause severe symptoms including congenital microcephaly and Guillain-Barré syndrome. The positive single-stranded RNA genome of the mosquito-borne ZIKV requires effective replication in two evolutionary distinct hosts - mosquitoes and primates. In addition to some of the viral proteins, the ZIKV genomic RNA and functional RNAs produced thereof aid in the establishment of productive infection and the evasion of host cell antiviral responses. ZIKV has evolved to contain a nucleotide composition and RNA modifications, such as methylation and the formation of G-quadruplexes that allow effective replication in both hosts. Furthermore, a number of host factors interact with the viral genome to modulate RNA replication. Importantly, the ZIKV genome produces non-coding subgenomic flavivirus RNA (sfRNA) due to stalling of host 5'- 3' ribonucleases on viral RNA structures in the 3' untranslated region (UTR). This sfRNA (sfRNA) exerts important proviral functions such as antagonizing the innate interferon response and RNA interference. Here, we discuss the ZIKV genomic RNA and functional RNAs thereof to assess their significance during ZIKV infection. Understanding the details of the ZIKV infection cycle will aid in the development of effective antiviral strategies and safe vaccines.