Prof. Dr. Reinhard Fischer (born 24.03.1962)
Diplom (Microbiology), University of Marburg, 1987
Ph.D. (Dr. rer. nat.) (Microbiology), University of Marburg, 1990
Postdoc (Microbiology), University of Marburg, 1991
Postdoc (Genetics), University of Georgia, Athens, Georgia, USA, 1992-1993
Research Associate at the Department of Microbiology of the Philipps-University of Marburg and at the Department of Biochemistry of the MPI Marburg, 1994-2004
Habilitation (Microbiology and Cell Biology), University of Marburg, 1998
Professor for Microbiology at the University of Karlsruhe, since 10/2004
DFG panel member since 2012.
Editorial boards: in the past: FEMS Microbiological Letter, Eukaryotic Cell, Fungal Genetics and Biology. currently: Molecular Microbiology, Molecular Genetics and Genomics, MBio, mSphere.
Funding: DFG, Landesstiftung Baden Württemberg, Fonds of the Chemical Industry, Humboldt Society, BMBF.
Karlsruhe Institute of Technology - KIT
Institute for Applied Bioscience
Department of Microbiology
Research Area: Cell Biology of Aspergillus nidulans
We are studying the filamentous fungus A. nidulans as a model for spore and mycotoxin formation as well as for polarized growth. A. nidulans produces asexual conidiospores for rapid distribution in the environment and sexual ascospores for long-term survival in soil. The decision between the developmental pathways, is determined by a number of environmental factors, one of which is light. Red-light represses sexual and induces asexual reproduction, and the effect can be reversed by far-red-light illumination. Thus, the system is reminiscent of the phytochrome system of plants. Phytochromes are photoreceptors that sense red and far-red light through photo-interconversion between two stable conformations. This distinct feature is mediated by a covalently bound linear tetrapyrrole chromophore. Phytochromes were thought to be confined to photosynthetic organisms including cyanobacteria, but have been recently discovered in heterotrophic bacteria and in fungi, where little is known about their functions. We discovered, that the A. nidulans phytochrome, PhsA, acts as red-light sensor and represses sexual development. We have characterized several other regulators in the past and will now try to link the phytochrome with the regulatory network.
Fungal development is linked to mycotoxin production. This link will be further investigated in A. nidulans at the molecular level.
In a third line of research, we are studying filamentous growth. This growth form enables fungi to extend indefinitely on solid surfaces. They represent a model for extremely polarized eukaryotic cells, similar to neurons in higher eukaryotes. The hyphal cell organisation requires very active intracellular transport. We are analyzing the role of microtubules and microtubule-dependent motor proteins and discovered a role for the kinesin-like motor KipA in microtubule organization.
Recent Publications (complete list)
Takeshita, N., Mania, D., Herrero de Vega, S., Ishitsuka, Y., Nienhaus, G.U., Podolski, M., Howard, J. & Fischer, R. (2013). The cell end marker TeaA and the microtubule polymerase AlpA contribute to microtubule guidance at the hyphal tip cortex of Aspergillus nidulans for polarity maintenance. J Cell Sci, 126, 5400-5411.
Manck, R., Ishitsuka, Y., Herrero de Vega, S., Takeshita, N., Nienhaus, U.G. & Fischer, R. (2015) Genetic evidence for a microtubule-capture mechanism during polar growth of Aspergillus nidulans. J Cell Sci, 128, 3569-3582.
Hedtke, M., Rauscher, S., Röhrig ,J., Rodriguez, J., Yu, Z., & Fischer, R. (2015) Light-dependent gene activation in Aspergillus nidulans is strictly dependent on phytochrome and involves the interplay of phytochrome and white-collar-regulated histone H3 acetylation. Mol Microbiol, 94, 733-745.
Ishitsuka, Y., Savage, N., Li, Y., Bergs, A., Kohler, D., Donnelly, R., Nienhaus, U., Fischer, R. & Takeshita, N. (2015) Super-resolution microscopy reveals a dynamic picture of cell polarity maintenance during directional growth. Science Advances, 1(10):e1500947.
Rauscher, S., Pacher, S., Hedtke, M., Kniemeyer, O. & Fischer, R. (2016) A phosphorylation code of the Aspergillus nidulans global regulator VelvetA (VeA) determines specific functions. Mol Microbiol, 99, 909-924.
Yu, Z, Armant, O. & Fischer, R. (2016) Fungi use the SakA (HogA) pathway for phytochrome-dependent light signaling. Nature Microbiol, 2016, 19. doi:10.1038/nmicrobiol.2016.19. highlight in Nature Reviews Microbiology: http://www.nature.com/nrmicro/journal/v14/n4/full/nrmicro.2016.36.html