Genetics
The Genetics division, led by Prof. Dr. Jürgen J. Heinisch, conducts basic research into stress response mechanisms and the associated signal transduction pathways in various yeasts and fungi as eukaryotic model organisms. Practical applications arise from biotechnological applications in wine and beer production, as well as in the clinical treatment of fungal infections.
A solid cell wall made of glucan, mannoproteins and chitin gives fungal cells their shape and stability. We investigate how yeast cells in particular adapt to external stress conditions and strengthen their cell walls via signalling pathways when necessary. In addition, we study cellular responses to oxidative stress, which plays a decisive role in cancer development, for example, as well as to light/dark phases in yeasts and fungi.
Regulation of cell wall synthesis
Yeast uses MAP kinase signalling pathways to respond to damage to the cell wall. The underlying mechanisms are very similar in yeast and humans. In most types of cancer, one of the components involved is defective in humans. Wine, beer and baker's yeast, Saccharomyces cerevisiae, in particular, serves as an excellent model organism that is easy to study and manipulate genetically.
Through our research, we have been able to contribute significantly to the elucidation of the CWI signalling pathway (‘cell wall integrity signalling’), in particular to the function of membrane-bound mechanosensors for the perception of external signals. Due to the vital importance of the cell wall for fungi, this research has potential applications in the search for antibiotics to combat the increasing number of deaths from fungal infections (approximately 2 million worldwide each year).
Oxidative stress
Due to their pronounced metabolism, cancer cells must be able to efficiently dispose of the oxygen radicals produced in the process. Here, too, the underlying mechanisms are very similar from yeast to humans. We have discovered a molecular switch (Rho5) that regulates both central metabolism and the specific response to oxidative stress in yeast. This protein is currently the focus of our research on yeast.
In addition, light also triggers oxidative stress when the filamentous fungus Ashbya gossypii alternates between dark and light growth phases (day/night rhythm). We also investigate these light-dependent regulations using genetic and cell biological methods.
Wine yeast Hanseniaspora uvarum
Grapes and grape must mainly contain the yeast H. uvarum, a so-called apiculatus yeast, which contributes essential aromatic substances to wine quality. We have sequenced the genome of this yeast and developed a series of molecular genetic methods for its investigation, research that was largely co-financed by the German Viticulture Research Association.
Proteins from humans, animals and plants
Over the past few decades, we have also used the pronounced ability of the yeast S. cerevisiae to undergo homologous recombination to support other research groups by specifically producing plasmids and investigating various proteins in yeast. This has enabled us to produce proteins in yeast that are involved in the development of Alzheimer's disease (Neurobiology), play an important role in heart development in fruit flies (Zoology) and are crucial for the disposal of oxygen radicals in plants and humans (Plant Physiology).
