AG Strauss


Mikrobielle Genetik - Fungal Genomics Unit

Research Focus

Fungal transcription factors and epigenetics

We try to understand at the molecular level how fungal transcription factors work in the context of chromatin to find their targets and to function according to the “instructions” they receive through signaling pathways from their environment. With these questions in mind we work on the saprophytic species Aspergillus nidulans and on two plant-pathogenic Fusarium species which infect wheat, maize and rice.

We use molecular genetic tools for functional studies of genes in our fungi and do lots of biochemistry work to isolate and to characterize the transcription factor proteins. Genome-wide studies of protein localization (ChIP-seq) and transcriptional activity (RNA-seq) are routinely used techniques in our lab. We also perform plant infection studies and use ChIP and RNA-seq to understand how these regulatory factors influence virulence of the pathogens. Finally, in cooperation with the AIT group (Markus Gorfer), we are interested to learn how such regulatory networks impose on the fitness and ecological functions of fungi in their environments.

Leiter: Univ.-Prof. Mag. Dr. Joseph Strauss

Current scientific projects and cooperations

The biosynthesis pathway and function of nitric oxide (NO*) – a short lived radical – on transcriptional networks in the nitrogen circuit and on developmental pathways in Aspergillus nidulans
Austrian Science Fund (FWF) project together with David Canovas  (Lise Meitner Project 2015-2017) in which we already determined that the nitrate reductase is one of the biosynthesis routes, but there are other pathways under examination which can contribute to NO* production in Aspergillus nidulans

Epigenetic regulation of  fungal pathogens: the role of histone regulators in the interactions between Fusarium species and crops plants
We have worked since many years on the chromatin-level regulation of primary metabolism, e.g. we showed that AreA, a broad-spectrum nitrogen regulator, is required for chromatin remodeling (Muro-Pastor et al., 1999, 2004) and that AreA brings histone acetylation to target promoters (Berger et al.,2006, 2008 ). Similarly we found a connection between heterochromatin and secondary metabolite gene expression (Bok et al., 2009, Reyes-Dominguez et al., 2010). In the frame of  a large Research Network funded by the FWF (Special Research Area SFB-Fusarium, 2016-2019) we can study selected histone modifiers in Fusarium and Aspergillus species for their role in regulation of metabolism and virulence.

Finding novel virulence factors by an epigenetic approach
A Lise-Meitner project (2017-2019) of the FWF to Lena Studt will dig deeper into the question how epigenetic factors influence virulence. Lena is using the rice pathogen Fusarium fujikuroi as a model system to ask which genes with known or presumed histone modification activities are vital for the infection process of this notorius pathogen. Results from these studies will help us to better understand the relevance of the epignetic dimension in host-pathogen interactions. 

Publikationen

ausgewählte Publikationen:

Jin Woo Bok, Yazmid Reyes-Dominguez, Yi-Ming Chiang, Edyta Szewczyk, Ashley D. Davidson, James F. Sanchez, Hsien-Chun Lo, Kenji Watanabe, Berl R. Oakley, Clay C. C. Wang, Joseph Strauss and Nancy P. Keller (2009). Chromatin-level regulation of cryptic biosynthetic gene clusters in Aspergillus nidulans. Nature Chem. Biol. (in press)

Asjad Basheer, Harald Berger, Yazmid Reyes-Dominguez and Joseph Strauss (2009). A library-based method to rapidly analyze chromatin accessibility at multiple genomic regions.
Nucleic Acid Research 37:e42

Harald Berger, Asjad Basheer, Sandra Böck, Thomas Dalik, Friedrich Altmann, and Joseph Strauss (2008). Dissecting individual steps of nitrogen transcription factor cooperation in the Aspergillus nidulans nitrate cluster. Mol. Microbiol 69: 1385 -1398

Yazmid Reyes-Dominguez, Narendja, F., Berger, H., Gallmetzer, A., Fernandez, R., Garcia, I., Scazzocchio, C. and Strauss, J. (2008)   Nucleosome positioning and histone H3-acetylation are independent processes in the Aspergillus nidulans prnD-prnB bidirectional promoter. Euk. Cell 7: 656-663

Andreas Bernreiter, Ana Ramon, Javier Fernández-Martínez, Harald Berger, Lidia Araújo-Bazan, Eduardo A. Espeso, Robert Pachlinger, Ingund Anderl , Claudio Scazzocchio and Joseph Strauss (2007).  Nuclear export of the transcription factor NirA is a regulatory checkpoint for nitrate induction in Aspergillus nidulans. Mol.Cell.Biol. 27: 791-802

Harald Berger, Robert Pachlinger, Igor Morozov, Mark Caddick, Sabine Goller, Frank Narendja and Joseph Strauss (2006). The GATA factor AreA regulates localization and in vivo binding site occupancy of the nitrate specific transcriptional activator NirA.  Mol. Microbiol. 59: 433-446

Elke Kainz, Andreas Gallmetzer, Christian Hatzl, Juergen H. Nett, Huijuan Li, Thorsten Schinko, Robert Pachlinger , Harald Berger,  Tillmann Gerngross, Stefan Wildt and Joseph Strauss (2007). N-glycan modification in Aspergillus species. Appl. Environ. Microbiol  74:1076-1086

Mark X Caddick, Meriel G Jones, J. Martin van Tonder1, Hélène Le Cordier1,Frank Narendja, Joseph Strauss, and Igor Y Morozov (2006) Opposing signals differentially regulate transcript stability in Aspergillus nidulans. Mol.Microbiol. 62: 509–519

Robert Pachlinger, Rudolf Mitterbauer, Gerhard Adam and Joseph Strauss (2005). Metabolically independent and accurately adjustable Aspergillus sp. expression system. Appl. Environ. Microbiol 71: 672-678

M.Isabel Muro Pastor, Joseph Strauss, Ana Ramón and Claudio Scazzocchio (2004). A paradoxical mutant GATA factor. Eukaryot Cell 3:393-405


Förderungsorganisationen

Kooperationen

  • Gerhard Adam, DAGZ, BOKU, Vienna
  • Christian Luschnig, DAGZ, BOKU, Vienna
  • Christian Obinger, Dept. of Chemistry, BOKU, Vienna
  • Rudolf Krska, F. Bertiller, R. Schuhmacher; IFA Tulln, Center for Analytical Chemistry
  • Clemes Peterbauer, Food Science & Technology
  • Katja Sterflinger, Biotechnology, Austrian Center of Biological Resources and Appl. Mycol.