Chikungunya virus adaptation to a mosquito vector correlates with only few point mutations in the viral envelope glycoprotein
Autor(es): Arias-Goeta Camilo, Moutailler Sara, Mousson Laurence, Zouache Karima, Thiberge Jean-Michel, Caro Valérie, Rougeon François, Failloux Anna-Bella
Resumo: Like most arthropod-borne viruses (arboviruses), chikungunya virus (CHIKV) is a RNA virus maintained in nature in an alternating cycle of replication between invertebrate - vertebrate hosts. It has been assumed that host alternation restricts arbovirus genome evolution - imposes fitness trade-offs. Despite their slower rates of evolution, arboviruses still have the capacity to produce variants capable to exploit new environments. To test whether the evolution of the newly emerged epidemic variant of CHIKV (E1-226V) is constrained by host alternation, the virus was alternately-passaged in hamster-derived BHK-21 cells - Aedes aegypti-derived Aag-2 cells. It was also serially-passaged in BHK-21 or Aag-2 cells to promote adaptation to one cell type - presumably, fitness cost in the bypassed cell type. After 30 passages, obtained CHIKV strains were genetically - phenotypically characterized using in vitro - in vivo systems. Serially- - alternately-passaged strains can be distinguished by amino-acid substitutions in the E2 glycoprotein, responsible for receptor binding. Two substitutions at positions E2-64 - E2-208 only lower the dissemination of the variant E1-226V in Ae. aegypti. These amino-acid changes in the E2 glycoprotein might affect viral infectivity by altering the interaction between CHIKV E1-226V - the cellular receptor on the midgut epithelial cells in Ae. aegypti but not in Aedesalbopictus.
Palavras-Chave: Arbovirus evolution; Genome stability; Host alternation; Vector adaptation
Imprenta: Infection, Genetics and Evolution, v. 24, p. 116-126, 2014
Identificador do objeto digital: 10.1016/j.meegid.2014.03.015
Descritores: Chikungunya virus - Arbovirus ; Chikungunya virus - Cell ; Chikungunya virus - Genome ; Chikungunya virus - Molecular structure ; Chikungunya virus - Pathogenesis ; Chikungunya virus - Proteins ; Chikungunya virus - RNA ; Chikungunya virus - Cytokines ; Chikungunya virus - Viral infections ; Chikungunya Virus - Virus ; Chikungunya virus - Chikungunya fever ; Chikungunya virus - Epidemic ; Chikungunya virus - Epidemiology ; Chikungunya virus - Public health
Data de publicação: 2014
