Velvet domain protein VosA represses the zinc cluster transcription factor SclB regulatory network for Aspergillus nidulans asexual development, oxidative stress response and secondary metabolism
Ontology highlight
ABSTRACT:
INSTRUMENT(S): Illumina HiSeq 4000
ORGANISM(S): Aspergillus nidulans
SUBMITTER: Florian Finkernagel
PROVIDER: E-MTAB-6996 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:The main objective was to identifiy genes related to scrA- extragenic suppression of crzA. Thus, through transcriptional profiling, we characterised the transcriptional basis of calcium tolerance in our mutant strain, M-NM-^TcrzA/scrA-. To evaluate the effect of calcium on global A. nidulans gene expression, we performed competitive microarray hybridizations using RNA obtained from the wild-type, M-NM-^TcrzA and M-NM-^TcrzA/scrA- strains before and after short pulses (10 and 30 minutes) of 200 mM calcium chloride. The experiment was further validated by real-time PCR. Two-condition experiment : A. nidulans wild-type, M-NM-^TcrzA and M-NM-^TcrzA/scrA- strains with 200 mM CaCl2 for 10 and 30 min at 30M-BM-0C and 150 rpm in 25 mL YAG medium. Firstly, the strains were grown overnight at 30M-BM-0C and 150 rpm in YAG medium (preculture). Afterwards, the medium was switched by a new media (25 mL) plus calcium and incubated as described above. Control condition refers to the preculture in YAG medium without further incubation.
2012-05-22 | E-GEOD-38131 | biostudies-arrayexpress
Project description:The formation of mitotically derived spores, called conidia, is a common reproductive mode in filamentous fungi, particularly among the large fungal class Ascomycetes. Asexual sporulation strategies are nearly as varied as fungal species; however, the formation of conidiophores, specialized multicellular reproductive structures, by the filamentous fungus Aspergillus nidulans has emerged as the leading model for understanding the mechanisms that control fungal sporulation. Initiation of A. nidulans conidiophore formation can occur either as a programmed event in the life cycle in response to intrinsic signals or to environmental stresses such as nutrient deprivation. In either case, a development-specific set of transcription factors is activated and these control the expression of each other as well as genes required for conidiophore morphogenesis. Recent progress has identified many of the earliest-acting genes needed for initiating conidiophore development and shown that there are at least two antagonistic signaling pathways that control this process. One pathway is modulated by a heterotrimeric G protein that when activated stimulates growth and represses both asexual and sexual sporulation as well as production of the toxic secondary metabolite, sterigmatocystin. The second pathway apparently requires an extracellular signal to induce sporulation-specific events and to direct the inactivation of the first pathway, removing developmental repression. A working model is presented in which the regulatory interactions between these two pathways during the fungal life cycle determine whether cells grow or develop.
| S-EPMC98905 | biostudies-literature
Project description:The NF-?B-like velvet domain protein VosA (viability of spores) binds to more than 1,500 promoter sequences in the filamentous fungus Aspergillus nidulans. VosA inhibits premature induction of the developmental activator gene brlA, which promotes asexual spore formation in response to environmental cues as light. VosA represses a novel genetic network controlled by the sclB gene. SclB function is antagonistic to VosA, because it induces the expression of early activator genes of asexual differentiation as flbC and flbD as well as brlA. The SclB controlled network promotes asexual development and spore viability, but is independent of the fungal light control. SclB interactions with the RcoA transcriptional repressor subunit suggest additional inhibitory functions on transcription. SclB links asexual spore formation to the synthesis of secondary metabolites including emericellamides, austinol as well as dehydroaustinol and activates the oxidative stress response of the fungus. The fungal VosA-SclB regulatory system of transcription includes a VosA control of the sclB promoter, common and opposite VosA and SclB control functions of fungal development and several additional regulatory genes. The relationship between VosA and SclB illustrates the presence of a convoluted surveillance apparatus of transcriptional control, which is required for accurate fungal development and the linkage to the appropriate secondary metabolism.
| S-EPMC6078315 | biostudies-literature
Project description:The Kae1/KaeA protein is a subunit of the highly evolutionarily conserved KEOPS complex (Kinase, Endopeptidase and Other Proteins of Small size). The Kae1/KaeA gene has been identified in all previously sequenced genomes of Archea, Bacteria and Eucaryota, except for the most reduced genomes. The KEOPS complex participates in the universal modification of the tRNA converting adenosine A37 to N6-threonylcarbamoyl adenosine (t6A37). This modification of A37, immediately 3’ of anticodons decoding ANN codons, is one of the few tRNA modifications present in all organisms and plays an extremely important role in the accuracy of the translation process. We characterized two mutations in kaeA of filamentous fungus Aspergillus nidulans that result in the derepression of arginine catabolic enzymes and also showed that kaeA is involved in the regulation of several other genes that control various domains of cellular metabolism. This suggests that kaeA has additional function apart from t6A37 modification. To support this hypothesis we looked for proteins interacting with KaeA.
2023-03-11 | PXD034554 | Pride
Project description:Genome wide transcriptional changes induced by various types of oxidative stresses as well as salt stress were studied in a DatfA mutant and the appropriate control A. nidulans strains. Although a significant number of stereotypically regulated genes was identified (Core Oxidative Stress Response or COSR genes) when the global transcriptional effects of five different oxidative stress conditions were compared the number of co-regulated genes decreased to 13 when NaCl stress was included into the analyses. The appearance of only a few co-regulated genes and the great number of genes regulated merely by one certain type of stress do not support the existence of a S. cerevisiae-type Environmental Stress Response in A. nidulans. Deletion of atfA, a true functional ortholog of fission yeastâs âall-purposeâ stress response transcription factor, increased the oxidative stress sensitivity of A. nidulans and affected the transcription of several genes under both unstressed and stressed conditions. The number of genes under AtfA control was quite stress-type dependent; e.g. deletion of atfA altered the transcription of a wide spectrum of genes under menadione sodium bisulfite stress but had only a minor effect on the transcriptome profiles when A. nidulans cultures were exposed to H2O2, tBOOH, NaCl and, especially, to diamide stress. These observations suggest that the function of AtfA in the regulation of various stress responses is much smaller than we thought before or other transcription factors can take over a number of AtfAâs functions when the atfA gene is deleted. It is noteworthy that both oxidative and salt stress induced the transcription of some secondary metabolite gene clusters and the deletion of atfA enhanced the stress responsiveness of further clusters. Surprisingly, certain clusters were down-regulated by the stress conditions tested and the majority of them were not stress-responsive at all. Therefore, stress dependent regulation seems to be a frequent but far not a general feature of the regulation of secondary metabolism in A. nidulans. 14 samples, 7 with the control strain and 7 with an DatfA strain (each series contains samples from untreated as well as menadione, low concentration hidrogen-peroxide, high concentration hidrogen-peroxide, tert-butylhydroperoxide, diamide and NaCl treated cultures)
2015-12-31 | E-GEOD-63019 | biostudies-arrayexpress
Project description:Transcriptome of A. nidulans R21 and ?gprH strains when grown on MM+1% glucose for 24 hours and transferred to MM with no carbon for 4 and 8 hours Three conditions: MM with glucose for 24 hours and MM without glucose for 4 and 8 hours. Two strains R21 and ?gprH. Three biological repetitions of each point.
2015-08-01 | E-GEOD-65282 | biostudies-arrayexpress
Project description:[This corrects the article DOI: 10.1371/journal.pgen.1007511.].
| S-EPMC6114284 | biostudies-literature
Project description:Beta-glucans are a heterologous group of fibrous glucose polymers that are a major constituent of cell walls in Ascomycetes and Basidiomycetes fungi. Synthesis of ? (1,3)- and (1,6)-glucans is coordinated with fungal cell growth and development, thus, is under tight genetic regulation. Here, we report that ?-glucan synthesis in both asexual and sexual spores is turned off by the NF-kB like fungal regulators VosA and VelB in Aspergillus nidulans. Our genetic and genomic analyses have revealed that both VosA and VelB are necessary for proper down-regulation of cell wall biosynthetic genes including those associated with ?-glucan synthesis in both types of spores. The deletion of vosA or velB results in elevated accumulation of ?-glucan in asexual spores. Double mutant analyses indicate that VosA and VelB play an inter-dependent role in repressing ?-glucan synthesis in asexual spores. In vivo chromatin immuno-precipitation analysis shows that both VelB and VosA bind to the promoter region of the ?-glucan synthase gene fksA in asexual spores. Similarly, VosA is required for proper repression of ?-glucan synthesis in sexual spores. In summary, the VosA-VelB hetero-complex is a key regulatory unit tightly controlling proper levels of ?-glucan synthesis in asexual and sexual spores.
| S-EPMC4426670 | biostudies-literature
Project description:Purpose: To explore conservation of gene regulation by the transcription factor clr-2/clrB in Neurospora crassa and Aspergillus nidulans Methods: mRNA from wild type and clr-2/clrB mutants were collected after a culture shift from sucrose/glucose to Avicel (crystaline cellulose) or no carbon media Results: We show that N. crassa and A. nidulans have similair global transcriptional responses to Avicel, with several hundred genes showing specific induction, though the induced genes are more specifically targeted at cellulose for N. crassa and more targeted at hemicellulose and pectin for A. nidulans. clr-2/clrB has a conserved fundamental function in cellulose induction, though the mechanism has diverged. Misexpression of clr-2 is sufficeint for inducer free cellulase secretion in N. crassa, but neither clrB or heterologous clr-2 is sufficient for inducer free cellulase secretion in A. nidulans. Conclusions: Our study demonstrates a conserved and essential role in cellulose utilization for the transcription factor clr-2 in filamentous ascomycetes and demonstrates that manipulation of clr-2 expression can be used to control cellulase expression in some species. Biological triplicates of liquid culture N. crassa and A. nidulans were harvested at 4 hours and 6 hours, respectively, after a switch to media of interest. Global mRNA abundances from liquid cultures of N. crassa and A. nidulans were measured by sequencing on the Illumina Genome Analyzer IIx and HiSeq2000 platforms.
2013-09-01 | E-GEOD-44100 | biostudies-arrayexpress
Project description:Transcriptional profiling of A. nidulans comparing the mutant strain alcAypkA grown on inducing or repressing conditions. The main objective was to identifiy genes related to ypkA gene function. The experiment was further validated by real-time PCR and enzymatic assay. Four-condition experiment: A. nidulans strains grown during 16 and 24 h at 37M-BM-0C in glucose 4% or glycerol 2% threonine 100mM.
2012-10-10 | E-GEOD-39755 | biostudies-arrayexpress