title: Genetic Drift during Systemic Arbovirus Infection of Mosquito Vectors Leads to Decreased Relative Fitness during Host Switching.
abstract: The emergence of mosquito-borne RNA viruses, such as West Nile virus (WNV), is facilitated by genetically complex virus populations within hosts. Here, we determine whether WNV enzootic (Culex tarsalis, Cx. quinquefasciatus, and Cx. pipiens) and bridge vectors (Aedes aegypti) have differential impacts on viral mutational diversity and fitness. During systemic mosquito infection, WNV faced stochastic reductions in genetic diversity that rapidly was recovered during intra-tissue population expansions. Interestingly, this intrahost selection and diversification was mosquito species dependent with Cx. tarsalis and Cx. quinquefasciatus exhibiting greater WNV divergence. However, recovered viral populations contained a preponderance of potentially deleterious mutations (i.e., high mutational load) and had lower relative fitness in avian cells compared to input virus. These findings demonstrate that the adaptive potential associated with mosquito transmission varies depending on the mosquito species and carries a significant fitness cost in vertebrates.
authors.affiliation: Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
authors.forename: Nathan D
authors.initials: ND
authors.lastname: Grubaugh
authors.affiliation: Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
authors.forename: James
authors.initials: J
authors.lastname: Weger-Lucarelli
authors.affiliation: Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
authors.forename: Reyes A
authors.initials: RA
authors.lastname: Murrieta
authors.affiliation: Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Fauver
authors.affiliation: Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
authors.forename: Selene M
authors.initials: SM
authors.lastname: Garcia-Luna
authors.affiliation: Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
authors.forename: Abhishek N
authors.initials: AN
authors.lastname: Prasad
authors.affiliation: Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA.
authors.forename: William C
authors.initials: WC
authors.lastname: Black
authors.affiliation: Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, CO 80523, USA. Electronic address: gregory.ebel@colostate.edu.
authors.forename: Gregory D
authors.initials: GD
authors.lastname: Ebel
mesh_terms: D000330:Aedes / Q000235:genetics / Q000821:virology*; D000818:Animals; D001103:Arboviruses / Q000235:genetics* / Q000502:physiology; D003465:Culex / Q000821:virology*; D040961:Genetic Drift; D014644:Genetic Variation; D000072138:Mosquito Vectors / Q000821:virology*; D009154:Mutation; D013045:Species Specificity; D014902:West Nile virus / Q000235:genetics* / Q000502:physiology