Epigenetic regulation of virulence in plant pathogenic fungi

Pathogenic fungi need to change their growth pattern depending on the stage of infection they are in (yeast-like, filamentous, specialized penetration structures, spores, etc.). This constant behavioral shift during infection is highly regulated. In our laboratory, we are interested in the mechanisms employed by pathogenic fungi to control these changes. Specifically, we are studying the epigenetic mechanisms controlling pathogenesis. In specific stages of the infective process, pathogenic fungi silence the portion of the genome that is not required by forming heterochromatin (a compact and inaccessible chromatin, transcriptionally inactive), which is converted to euchromatin (accessible and transcriptionally active) when required. In order to study these processes, we currently use the model organism Ustilago maydis, a corn pathogen that causes the corn smut disease. This fungus lacks most of the known mechanisms for heterochromatin formation, which is allowing us to discover new epigenetic mechanisms used by pathogenic fungi to silence the virulence program. For our studies, we use molecular biology techniques for editing microorganisms’ genome, Mass Spectrometry, RNA-seq, and ChIP-seq, among others, in combination with cellular biology techniques such as fluorescence microscopy.