Genome-wide analysis of DNA methylation Metarhizium robertsii. Metarhizium robertsii

Genome-wide analysis of DNA methylation for different stages of Metarhizium robertsii Overall design: Metarhizium robertsii is a well-characterized entomopathogenic fungus that used as an important alternative to chemical insecticides in programs of agricultural pest and disease vector control. Metarhizium conidia are involved in fungal propagation and also are responsible for host infection. Despite their importance, several aspects of conidial biology, including their DNA methylome, are still unknown. Here, we performed a comparative DNA methylomic analysis of the conidia and mycelia of an M. robertsii strain at single-base resolution. The results showed that approximately 0.39 % of cytosines are methylated in conidia, lower than the DNA methylation level (0.42 %) in mycelia. DNA methylation in M. robertsii undergoes genome-wide reprogramming during fungal development. Gene Ontology (GO) analysis and KEGG analysis of DMR-associated genes revealed that amino acid, carbohydrate, fatty acid metabolism and ATP synthase were involved in energy synthesis and metabolism in M. robertsii. Intriguingly, transcription is influenced by genic methylation: genes with moderately methylated in promoter regions are likely to be enhanced transcription, whereas genes at either extreme are least likely. These patterns contrast with those found previously in other eukaryotes. Especially, some differentially methylated genes which are essential for energy synthase and metabolism have been found in this study, such as acetyl-CoA acetyltransferase and ATP synthase H chain. We propose that genes involved in energy synthesis and metabolic activity are developmentally regulated primarily by promoter DNA methylation.