| Title: | The master regulator MAT1-1-1 of fungal mating binds to its targets via a conserved motif in the human pathogen Aspergillus fumigatus |
| Author(s): | Ramsak B; Markau J; Pazen T; Dahlmann TA; Krappmann S; Kuck U; |
| Address: | "Allgemeine und Molekulare Botanik, Ruhr-Universitat Bochum, 44780 Bochum, Germany. Mikrobiologisches Institut - Klinische Mikrobiologie, Immunologie und Hygiene, Universitatsklinikum Erlangen und Friedrich-Alexander-Universitat (FAU) Erlangen-Nurnberg, 91054 Erlangen, Germany" |
| DOI: | 10.1093/g3journal/jkaa012 |
| ISSN/ISBN: | 2160-1836 (Electronic) 2160-1836 (Linking) |
| Abstract: | "Mating-type transcription factors are master regulators of sexually related signal transduction pathways in fungi; however, their recognition of specific DNA sequences from target genes is widely undetermined. Here, we identified and characterized the DNA-binding sequence of the MAT1-1-1 alpha-box domain transcription factor from the human pathogen Aspergillus fumigatus. In order to explore MAT1-1-1 DNA-binding targets, we used the previously reported MAT1-1-1 binding motif from Penicillium chrysogenum, in a bioinformatics approach. We identified 18 A. fumigatus genes carrying the MAT1.1 sequence in their upstream region, among them genes for the alpha-pheromone precursor (PpgA), G-protein-coupled pheromone receptor (PreA), and for TomA, an unidentified protein. To validate our prediction further, quantification of transcript levels showed a decrease in expression of ppgA, tomA, and others in a MAT1-1 deletion strain. For a functional analysis of the binding sites, truncated variants of the A. fumigatus MAT1-1-1 gene were introduced into Escherichia coli for heterologous expression. The yield of recombinant protein was further optimized for the AfMAT1-1-178-235 variant that harbors an extended alpha-box domain. AfMAT1-1-178-235 bound to a subset of the most strongly upregulated genes: ppgA, preA, and tomA. The DNA-binding specificity was confirmed by testing mutated binding sequences, as well as performing competition experiments with specific and non-specific sequences. Finally, equilibrium dissociation constants of 1.83 +/- 0.1 and 1.45 +/- 0.26 microM were determined for AfMAT1-1-178-235 and fusion protein GST-AfMAT1-1-178-235. Collectively, these findings provide further insights into AfMAT1-1-1-mediated gene expression and imply that alpha-box domain regulators from other members of Eurotiales control fungal development in a conserved manner" |
| Keywords: | "*Aspergillus fumigatus/genetics Fungal Proteins/genetics Fungi *Genes, Mating Type, Fungal Transcription Factors/genetics Escherichia coli protein synthesis DNA-binding motif human pathogen Aspergillus fumigatus mating type transcription factor;" |
| Notes: | "MedlineRamsak, Barbara Markau, Jessica Pazen, Tobias Dahlmann, Tim A Krappmann, Sven Kuck, Ulrich eng Research Support, Non-U.S. Gov't England 2021/02/19 G3 (Bethesda). 2021 Feb 9; 11(2):jkaa012. doi: 10.1093/g3journal/jkaa012" |
