Predicting lifestyle and host from positive selection data and genome properties in oomycetes

Abstract

AbstractBackgroundHost and niche shifts are a source of genomic and phenotypic diversification as evidenced in parasitism. Exemplary is core metabolism reduction as parasites adapt to a particular host, while the accessory genome often maintains a high degree of diversification. However, selective pressures acting on the genome of organisms that have undergone lifestyle or host change have not been fully investigated.ResultsHere, we developed a comparative genomics approach to study underlying adaptive trends in oomycetes, a eukaryotic phylum with a broad range of economically important plant and animal parasitic lifestyles. Our analysis reveals converging evolution on biological processes for oomycetes that have similar lifestyle. Besides, we find that certain functions, in particular carbohydrate metabolism, transport, and signaling, are important for host and environmental adaption in oomycetes.DiscussionGiven the high correlation between lifestyle and genome properties in our oomycete dataset and the convergent evolution of fungal and oomycete genomes, we have developed a model that predicts plant pathogen lifestyles with high accuracy based on functional annotations. Understanding how genomes and selective pressures correlate with lifestyle may be crucial to identify new emerging diseases and pandemic threats.