Project description:Transcriptome of A. nidulans ∆pkaA strain when grown on complete media (CM) and transferred to minimal media plus avicel as a sole carbon source for 8 and 24 hours
Project description:Transcriptome of A. nidulans TNO2a3 and ∆ptpB strains when grown on minimal media plus casaminoacids and transferred to minimal media plus glucose as a sole carbon source for 4 hours
Project description:Transcriptome of A. nidulans TNO2a3, ∆snfA and ∆schA strains when grown on complete media (CM) and transferred to minimal media plus avicel as a sole carbon source for 8 and 24 hours.
Project description:Transcriptome of A. nidulans TNO2A3, ∆msbA and ∆MHD strains when grown on complete media (YUU) and transferred to minimal media plus avicel as a sole carbon source for 24 hours
Project description:Transcriptional profiling of A. nidulans comparing starvation for 0 (reference), 12 and 24 h. The main objective was to identify genes specifically regulated during starvation by atmA and xprG. The results of the experiment were further validated by real-time PCR. Experimental procedure: Three A. nidulans strains were used in this study: WT, delta atmA and delta xprG. Strains were grown on minimal medium for 24 h (0 h starvation reference), then exposed to 12 and 24 h starvation. atmA: ATM, Ataxia-Telangiectasia mutated; Malavazi, I., Savoldi, M., Da Silva Ferreira, M. E., Soriani, F. M., Bonato, P. S., De Souza Goldman, M. H. and Goldman, G. H. (2007), Transcriptome analysis of the Aspergillus nidulans AtmA (ATM, Ataxia-Telangiectasia mutated) null mutant. Molecular Microbiology, 66: 74-99 (PMID 17880424). xprG: extracellular protease; Margaret E. Katz, Karen-Ann Gray, Brian F. Cheetham, (2006) The Aspergillus nidulans xprG (phoG) gene encodes a putative transcriptional activator involved in the response to nutrient limitation, Fungal Genetics and Biology, 43, 190-199 (PMID 16464624).
Project description:In Aspergillus nidulans, nitrogen and carbon metabolism are under the control of wide-domain regulatory systems, including nitrogen metabolite repression, carbon catabolite repression. 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.
Project description:Glutathione (GSH) is an abundant and widely distributed antioxidant in fungi. Hence, understanding cellular GSH metabolism is of vital importance to deciphering redox regulation in these microorganisms. In this study, we generated dugB (AN1879), dugC (AN1092), and dugB dugC double deletion mutants which display disruption of the GSH degradation pathway in Aspergillus nidulans. Deletion of dugB, dugC or both resulted in a moderate increase in GSH content under growing conditions and substantially slowed down the depletion of GSH pools under carbon starvation. Inactivation of dug genes caused reduced accumulation of reactive oxygen species, decreased autolytic cell wall degradation and extracellular enzyme production, increased sterigmatocystin formation but decreased viability in starving cultures. Changes in the transcriptomes suggested that enzyme secretions were controlled at post transcriptional level. In contrast, secondary metabolite production was also regulated at the level of mRNA abundance. Based on these findings, we suggest that GSH connects starvation and redox regulation to each other: A. nidulans cells utilize GSH as stored carbon source during starvation. The reduction of GSH contents of cells alters the redox state activating regulatory pathways responsible for carbon starvation stress responses. Under glucose rich conditions, inactivation of dug genes reduced conidia production of surface cultures, disturbed sexual development and down-regulated the transcription of genes encoding MAP kinase pathway proteins (e.g. steC, sskB, pbsA, hogA, mkkA) or proteins involved in the regulation of conidiogenesis or sexual differentiation (e.g. flbA,C,E, nosA, rosA, nsdC,D). These finding indicates that the authority of redox regulation goes far beyond the protection against redox stress; it affects development, stress responses (other than redox stress) and secondary metabolism as well.
Project description:Although tyrosol is a quorum-sensing molecule of Candida species, it has antifungal activity at supraphysiological concentrations. Here, we studied the effect of tyrosol on the physiology and genome-wide transcription of Aspergillus nidulans to gain insight into the background of the antifungal activity of this compound. Tyrosol efficiently reduced germination of conidia and the growth on various carbon sources at a concentration of 35 mM. The growth inhibition was fungistatic rather than fungicide on glucose and was accompanied with downregulation of 2199 genes related to e.g. mitotic cell cycle, glycolysis, nitrate and sulphate assimilation, chitin biosynthesis, and upregulation of 2250 genes involved in e.g. lipid catabolism, amino acid degradation and lactose utilization. Tyrosol treatment also upregulated genes encoding glutathione-S-transferases (GSTs), increased specific GST activities and the glutathione (GSH) content of the cells, suggesting that A. nidulans can detoxify tyrosol in a GSH-dependent manner even though this process was weak. Tyrosol did not induce oxidative stress in this species, but upregulated “response to nutrient levels”, “regulation of nitrogen utilization”, “carbon catabolite activation of transcription” and “autophagy” genes. Tyrosol may have disturbed the regulation and orchestration of cellular metabolism, leading to impaired use of nutrients, which resulted in growth reduction.
