The role of the GATA transcription factor AreB in regulation of nitrogen and carbon metabolism in Aspergillus nidulans

Abstract

In Aspergillus nidulans , nitrogen and carbon metabolism are under the control of wide-domain regulatory systems, including nitrogen metabolite repression, carbon catabolite repression and the nutrient starvation response. Transcriptomic analysis of the wild type strain grown under different combinations of carbon and nitrogen regimes was performed, to identify differentially regulated genes. Carbon metabolism predominates as the most important regulatory signal but for many genes, both carbon and nitrogen metabolisms coordinate regulation. To identify mechanisms coordinating nitrogen and carbon metabolism, we tested the role of AreB, previously identified as a regulator of genes involved in nitrogen metabolism. Deletion of areB has significant phenotypic effects on the utilization of specific carbon sources, confirming its role in the regulation of carbon metabolism. AreB was shown to regulate the expression of areA , tamA, creA, xprG and cpcA regulatory genes suggesting areB has a range of indirect, regulatory effects. Different isoforms of AreB are produced as a result of differential splicing and use of two promoters which are differentially regulated by carbon and nitrogen conditions. These isoforms are likely to be functionally distinct and thus contributing to the modulation of AreB activity.

Genome-wide Identification of the Aspergillus oryzae GATA Transcription Factor Gene Family and expression Analysis under Temperature or Salt Stresses

“…For example, the expression level of AoAreB and AoAreA showed opposite trends at high temperature (40 ℃) compared with CK (30 ℃) in A. oryzae, while AoAreB and AoAreA were inhibited under high salt stresses. AreA and AreB function as positive and negative transcriptional regulators participating in regulating nitrogen metabolism and carbon metabolism in Fusarium fujikuroi and Aspergillus nidulans [11,12,31], which indicated AoAreB and AoAreA might also act as positive and negative transcriptional regulators under temperature and salt stresses. The AoNsdD and AoSnf5, clustering into NSDD subgroup in the NJ_tree (Fig.…”

“…Apart from their active involvement in nitrogen metabolism, owering growth and development in plants, GATA TFs also play a key role in response to various environmental stimuli stress such as salinity, drought, and temperature stresses [8,9]. Diverse roles governed by GATA TFs in fungus mainly involved in nitrogen regulation and light responses, regulation of sexual and/or asexual reproduction, and secondary metabolism [10,11,12,13]. Research has demonstrated that the AreB and AreA GATA TFs are regulators that are not only involved in the nitrogen and carbon metabolism, but also in the control of several complex cellular processes such as transport and secondary metabolism in lamentous fungi [11,12].…”

“…Diverse roles governed by GATA TFs in fungus mainly involved in nitrogen regulation and light responses, regulation of sexual and/or asexual reproduction, and secondary metabolism [10,11,12,13]. Research has demonstrated that the AreB and AreA GATA TFs are regulators that are not only involved in the nitrogen and carbon metabolism, but also in the control of several complex cellular processes such as transport and secondary metabolism in lamentous fungi [11,12]. The SreA involves in regulation of siderophore biosynthesis and the control of iron uptake [10,14], and NsdD is a global regulator that regulates sexual and/or asexual reproduction and the production of SMs in A. nidulans and A. fumigatus [15,16].…”

“…The previous studies have demonstrated that GATA TFs mainly involved in regulation of various temperature and salt stimuli stress signaling in plants and few fungi [6,8,9,18]. Although the FTFD and Tetsuo Kobayashi et al publicized six A. oryzae GATA TFs which may involve in nitrogen regulation and light responses, regulation of sexual and/or asexual reproduction, and secondary metabolism [11,12,26], there is lack of research on a comprehensive analysis of GATA TF structural characteristics, evolutionary features, conserved motifs and expression level under different environmental stress factors in A. oryzae. Therefore, the aim of this study was to identify the GATA TFs in the whole A. oryzae 3.042 genome, to analyze their domain structure, evolutionary features, and conserved motifs, and to provide a basis for the cloning of GATA TFs in A. oryzae.…”

The Aspergillus fumigatus Phosphoproteome Reveals Roles of High-Osmolarity Glycerol Mitogen-Activated Protein Kinases in Promoting Cell Wall Damage and Caspofungin Tolerance

“…This included the AreB (AFUB_029020) GATA zinc finger transcription factor, which negatively regulates nitrogen catabolism (65). The A. nidulans areB null mutant has significant phenotypic effects on the utilization of specific carbon sources, confirming its role in the regulation of carbon metabolism (66). Considering the importance of carbon source assimilation in the remodeling of the cell wall could explain why in A. fumigatus AreB is important for the cell wall damage response.…”