title: Reassortment and distinct evolutionary dynamics of Rift Valley Fever virus genomic segments.
abstract: Rift Valley Fever virus (RVFV) is a member of Bunyaviridae family that causes a febrile disease affecting mainly ruminants and occasionally humans in Africa, with symptoms that range from mid to severe. RVFV has a tri-segmented ssRNA genome that permits reassortment and could generate more virulent strains. In this study, we reveal the importance of reassortment for RVFV evolution using viral gene genealogy inference and phylodynamics. We uncovered seven events of reassortment that originated RVFV lineages with discordant origins among segments. Moreover, we also found that despite similar selection regimens, the three segments have distinct evolutionary dynamics; the longer segment L evolves at a significant lower rate. Episodes of discordance between population size estimates per segment also coincided with reassortment dating. Our results show that RVFV segments are decoupled enough to have distinct demographic histories and to evolve under different molecular rates.
authors.affiliation: Laboratory of Molecular Evolution and Bioinformatics, Department of Microbiology, Biomedical Sciences Institute, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Caio C M
authors.initials: CC
authors.lastname: Freire
authors.affiliation: Laboratory of Molecular Evolution and Bioinformatics, Department of Microbiology, Biomedical Sciences Institute, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Atila
authors.initials: A
authors.lastname: Iamarino
authors.affiliation: Institut Pasteur de Dakar, Dakar, Senegal.
authors.forename: Peinda O Ly
authors.initials: PO
authors.lastname: Soumaré
authors.affiliation: Institut Pasteur de Dakar, Dakar, Senegal.
authors.forename: Ousmane
authors.initials: O
authors.lastname: Faye
authors.affiliation: Institut Pasteur de Dakar, Dakar, Senegal.
authors.forename: Amadou A
authors.initials: AA
authors.lastname: Sall
authors.affiliation: Laboratory of Molecular Evolution and Bioinformatics, Department of Microbiology, Biomedical Sciences Institute, University of Sao Paulo, Sao Paulo, Brazil.
authors.forename: Paolo M A
authors.initials: PM
authors.lastname: Zanotto
mesh_terms: D005075:Biological Evolution; D014644:Genetic Variation; D016679:Genome, Viral; D010802:Phylogeny; D016865:Reassortant Viruses / Q000235:genetics*; D012296:Rift Valley fever virus / Q000235:genetics*; D012641:Selection, Genetic; D013997:Time Factors