Chromatin composition at fungal gene clusters

Fungi are essential for global nutrient cycling and play vital roles in soil biology and plant litter decomposition. Importantly, the vast majority of plant diseases are caused by fungal pathogens thus making them an important group of economically relevant microorganisms. In all habitats, fungi must compete with other microbes for nutrients, water and space. One means of denying access to their own resources is to inhibit competitors growth and proliferation by the formation of bioactive metabolites such as antibiotics or mycotoxins. Some years ago we have shown that the production of these compounds is under the control of genomic silencing mechanisms and we found out with our collaborators that competition between bacteria and fungi generates a specific chromatin language that leads to expression of antimicrobial compounds. In this project we want to better understand this regulatory mechanism and plan to dissect one of the main regulators of mycotoxin and antibiotic production. The protein belongs to the family of histone demethylases and we will apply genetic, genomic and biochemical tools to better understand its function. The outcome of this project will not only provide us with a more detailed picture of the chromatin- based regulation of fungal secondary metabolism but will also add new knowledge on the functional domains of this regulator which in humans is overexpressed in a number of cancers and thus likely involved in their generation.

Although molds have a "bad reputation" among the public, they are extremely important for the functioning of the natural nutrient cycle on earth because they play an essential role in the recycling of plant biomass, for example. It is also important to mention that the vast majority of plant diseases are caused by fungi, which also makes molds economically important microorganisms for food security. And new dangers are posed by previously unknown fungal diseases that are now appearing in our latitudes due to climate change and they pose a massive threat to plants and animals. In all their habitats, these micro-fungi naturally compete with other organisms for nutrients, water and space. In order to assert themselves in the best possible way and to suppress the defense of plants during infection, these fungi produce various bioactive substances such as antibiotics or fungal toxins. A few years ago, we discovered that the production of these substances in fungi is under epigenetic control. In the research project that has now been completed, we have further investigated the epigenetic mechanisms in fungi. This involved developing a new epigenetic investigation method that can be used to precisely target specific regions in the fungal chromosomes. In an international cooperation, a completely new regulatory unit for the epigenetic processes was found, without which the fungus cannot produce toxins and cannot infect plants. Further details on the biosynthetic pathways and on interactions with plants, other fungi and bacteria were collected and precisely characterized down to the molecular level. Several Early-Stage Researchers and students worked for this project and have been educated and skilled during this time. In total, 16 scientific articles were published in high-ranking international journals and media articles were written on research into epigenetics in fungi as part of this project. The results of this project have not only provided a more precise picture of the function of epigenetic regulators during fungal growth and the production of fungal toxins, but have also contributed to better control fungal diseases in humans, animals and plants in the future.