Phytopathogen-induced changes to plant methylomes

Abstract

DNA methylation is a dynamic and reversible type of epigenetic mark that contributes to cellular physiology by affecting transcription activity, transposon mobility and genome stability. When plants are infected with pathogens, plant DNA methylation patterns can change, indicating an epigenetic interplay between plant host and pathogen. In most cases methylation can change susceptibility. While DNA hypomethylation appears to be a common phenomenon during the susceptible interaction, the levels and patterns of hypomethylation in transposable elements and genic regions may mediate distinct responses against various plant pathogens. The effect of DNA methylation on the plant immune response and other cellular activities and molecular functions is established by localized differential DNA methylation via cis-regulatory mechanisms as well as through trans-acting mechanisms. Understanding the epigenetic differences that control the phenotypic variations between susceptible and resistant interactions should facilitate the identification of new sources of resistance mediated by epigenetic mechanisms, which can be exploited to endow pathogen resistance to crops.

Local parasite pressures and host genotype modulate epigenetic diversity in a mixed‐mating fish

“…Increasing evidence suggests that epigenetic mechanisms, including genome‐wide DNA methylation, are involved in host–pathogen interactions (Gómez‐Díaz, Jordà, Peinado, & Rivero, ; Hu, Pérez‐Jvostov, Blondel, & Barrett, ), but the mechanisms are better known in plants than in animals (Annacondia, Mageroy, & Martinez, ; Gómez‐Díaz et al, ; Hewezi, Pantalone, Bennett, Neal Stewart, & Jr., Burch‐Smith TM, ). Pathogenic infection in plants can result in hypomethylation of resistance‐related genes but in hypermethylation at genome‐wide level (Peng & Zhang, ).…”

Local parasite pressures and host genotype may modulate epigenetic diversity in a mixed-mating fish

“…Increasing evidence suggests that epigenetic mechanisms, including genome-wide DNA methylation, are involved in host-pathogen interactions (Gómez-Díaz et al 2012; Hu et al 2018), but the mechanisms are better known in plants than in animals (Annacondia et al 2018; Hewezi et al 2018; Gómez-Díaz et al 2012). Mixed-mating organisms represent ideal models to test the associations between genetic and epigenetic variation with pathogen pressures because selfed and outcrossed offspring naturally coexist, usually displaying very different levels of genetic diversity.…”

Expression of disease resistance in genetically modified grapevines correlates with the contents of viral sequences in the T-DNA and global genome methylation

“…In plants, the introduction and expression of foreign sequences and the presence of RNA pathogens has led to the discovery of various homology-dependent gene-silencing mechanisms associated to changes in DNA methylation (Hewezi et al 2017;Matzke et al 2015). Three context of DNA methylation have been described in plants; CG, CHG, and CHH (where H is A, C or T), requiring distinct mechanisms for their establishment and maintenance, and showing different effects on DNA sequences (Matzke et al 2015).…”

“…Three context of DNA methylation have been described in plants; CG, CHG, and CHH (where H is A, C or T), requiring distinct mechanisms for their establishment and maintenance, and showing different effects on DNA sequences (Matzke et al 2015). Frequently, gene expression is shut down in genome regions methylated for all three contexts, and the repression can sometimes be extended to neighboring locations (Hewezi et al 2017;Matzke et al 2015). Global genome methylation has been associated with gene expression changes in developmental control, evolutionary processes, and responses to environmental conditions in plants (Lewsey et al 2016;Matzke et al 2015).…”