Epigenetic Regulation of Verticillium dahliae Virulence: Does DNA Methylation Level Play A Role?

Abstract

Verticillium dahliae is the etiological agent of Verticillium wilt of olive. The virulence of Defoliating V. dahliae isolates usually displays differences and high plasticity. This work studied whether an epigenetic mechanism was involved in this plasticity. An inverse correlation between virulence and DNA methylation of protein-coding genes was found. A set of 831 genes was selected for their highly consistent inverse methylation profile and virulence in the five studied isolates. Of these genes, ATP-synthesis was highly represented, which indicates that the more virulent D isolates are, the more energy requirements they may have. Furthermore, there were numerous genes in the protein biosynthesis process: genes coding for the chromatin structure, which suggests that epigenetic changes may also affect chromatin condensation; many transmembrane transporter genes, which is consistent with denser compounds, traffic through membranes in more virulent isolates; a fucose-specific lectin that may play a role in the attachment to plant cell walls during the host infection process; and pathogenic cutinases that facilitate plant invasion and sporulation genes for rapid spreading alongside plants. Our findings support the notion that differences in the virulence of the Defoliating V. dahliae isolates may be controlled, at least to some extent, by an epigenetic mechanism.

Population-level transposable element expression dynamics influence trait evolution in a fungal crop pathogen

“…Assessing the landscape of TEs in the genome helps distinguish between silenced and deactivated TEs from copies with the potential to proliferate. Genomes of fungal pathogens including the plant, animal, and the broad host range pathogens carry large TE-rich regions that also encode virulence-related genes ( 25 – 28 ). The TE-rich regions influence genome plasticity and effector expression in the rice blast pathogen Magnaporthe oryzae ( 29 – 31 ).…”

Population-level transposable element expression dynamics influence trait evolution in a fungal crop pathogen

“…The distribution of TEs in fungal genomes can alter gene expression including the expression of small secreted proteins acting as virulence factors, also called effectors. The soil-borne fungal plant pathogen, Verticillium dahliae carries a dynamic TE-rich region encoding virulence-related genes (Ramírez-Tejero et al, 2020; Torres et al, 2021). TEs also played a key role in genome plasticity and induced chromosomal rearrangement in the rice blast pathogen Magnaporthe oryzae .…”