Santiago F. Elena
CSIC professor at the IBMCP.CSIC
IBMCP
Evolutionary Systems Virology
Campus UPV CPI 8E, Ingeniero Fausto Elio s/n
Valencia, 46022
Spain
Website
Abstracts (first author)
Empirical fitness landscapes reveals a limited number of accessible adaptive pathways for an RNA virus
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Summary:
RNA viruses are the main source of emerging infectious diseases owed to the evolutionary potential bestow by their fast replication, large population sizes and high mutation and recombination rates. However, an equally important parameter, which is usually neglected, is the topography of the fitness landscape, that is, how many fitness maxima exist and how well connected they are, which determines the number of accessible evolutionary pathways. To address this question, we have reconstructed a fitness landscape describing the adaptation of Tobacco etch potyvirus to a new host, Arabidopsis thaliana. Two fitness traits were measured for most of the genotypes in the landscape, infectivity and virus accumulation. We found prevailing epistatic effects between mutations in the early steps of adaptation, while independent effects became more common at latter stages. Results suggest that the landscape was rather smooth, with a high number of potential neutral paths and a single fitness peak.