TY - JOUR T1 - <em>Botrytis cinerea</em> loss and restoration of virulence during <em>in vitro</em> culture follows flux in global DNA methylation JF - bioRxiv DO - 10.1101/059477 SP - 059477 AU - James Breen AU - Luis Alejandro Jose Mur AU - Anushen Sivakumaran AU - Aderemi Akinyemi AU - Michael James Wilkinson AU - Carlos Marcelino Rodriguez Lopez Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/08/26/059477.abstract N2 - Pathogenic fungi can lose virulence after protracted periods of culture but little is known of the underlying mechanisms. Here we present the first single-base resolution methylome for the plant pathogen B. cinerea and identify differentially methylated genes/genomic regions associated with virulence erosion.Cultures were maintained for eight months with subcultures and virulence testing every month. Methylation-sensitive amplified polymorphisms were performed at monthly intervals to characterise global changes to the pathogen’s genome during culture and also on DNA from mycelium inoculated onto Arabidopsis thaliana after eight months in culture. Characterisation of culture-induced epialleles was assessed by whole-genome re-sequencing and whole-genome bisulfite sequencing.Virulence declined with time in culture and recovered after inoculation on A. thaliana. Variation detected by methylation-sensitive amplified polymorphisms followed virulence changes during culture. Whole-genome (bisulfite) sequencing showed marked changes on global and local methylation during culture but no significant genetic changes.We imply that virulence is a non-essential plastic character that is at least partly modified by changing levels of DNA methylation during culture. We hypothesise that changing DNA methylation during culture may be responsible for the high virulence/low virulence transition in B. cinerea and speculate that this may offer fresh opportunities to control pathogen virulence. ER -