Experimental host-range expansion in a plant RNA virus: an interplay between viral fitness and regulation of host’s transcriptome

Abstract

Experimental evolution offers a testing ground for evolutionary hypotheses. The evolution of generalist and specialist pathogen strains, a process that is in the basis of viral emergence, is of particular interest. We are exploring the extent in which host genetic variability for susceptibility to infection influences the degree of virus local adaptation. Experiments resulted in higher viral fitness on the local host, though some hosts selected for costless generalists. We compared the transcriptomes of plants infected with ancestral or evolved viruses and found that generalists manipulate similar sets of genes across host genotypes while specialists do not so.