Genome-wide analyses for the cellular and chemical development regulator WetA in Aspergillus flavus
Ontology highlight
ABSTRACT:
ORGANISM(S): Aspergillus flavus
PROVIDER: GSE95711 | GEO | 2017/06/04
SECONDARY ACCESSION(S): PRJNA378205
REPOSITORIES: GEO
Similar Datasets
Project description:Asexual development is fundamental to the ecology and lifestyle of filamentous fungi and can facilitate both plant and human infection. In the filamentous fungal genus Aspergillus, the production of asexual spores is primarily governed by the BrlA-AbaA-WetA central regulatory cascade. The final step in this cascade, which is controlled by the WetA protein, not only governs cellular development (i.e., the morphological differentiation of spores) but also ensures its coupling with chemical development (i.e., the coordinated production and deposition of diverse secondary metabolites, such as aflatoxins, into spores). While the wetA gene is conserved across the genus Aspergillus, the structure and degree of conservation of the BrlA-AbaA-WetA regulatory cascade and the broader wetA gene regulatory network (GRN) remain largely unknown. We carried out comparative transcriptome analyses between wetA null mutant and wild type (WT) asexual spores in three representative species spanning the diversity of the genus Aspergillus: the genetic model A. nidulans, the agricultural pest A. flavus, and the human pathogen A. fumigatus. We discovered that WetA regulates asexual sporulation in all three species via a negative feedback loop that represses BrlA, the cascade’s first step. Furthermore, ChIP-seq experiments in A. nidulans asexual spores suggest that WetA is a DNA-binding protein that interacts with a novel regulatory element, which we term the WetA Response Element (WRE). Interestingly, the WRE is found completely conserved in the non-coding region upstream of the wetA translation start site of many diverse Aspergillus genomes. In contrast, several global transcriptional regulators, most notably those in the velvet complex (veA, velB, and laeA) known to regulate the coupling between asexual development and production of secondary metabolites, show species-specific regulatory patterns. These results suggest that the BrlA-AbaA-WetA cascade’s regulatory role in cellular and chemical development of asexual spores is functionally conserved, but that the WetA-associated GRN has diverged during Aspergillus evolution. This entry is for the RNA-seq data.
2018-07-24 | GSE114143 | GEO
Project description:Asexual development is fundamental to the ecology and lifestyle of filamentous fungi and can facilitate both plant and human infection. In the filamentous fungal genus Aspergillus, the production of asexual spores is primarily governed by the BrlA-AbaA-WetA central regulatory cascade. The final step in this cascade, which is controlled by the WetA protein, not only governs cellular development (i.e., the morphological differentiation of spores) but also ensures its coupling with chemical development (i.e., the coordinated production and deposition of diverse secondary metabolites, such as aflatoxins, into spores). While the wetA gene is conserved across the genus Aspergillus, the structure and degree of conservation of the BrlA-AbaA-WetA regulatory cascade and the broader wetA gene regulatory network (GRN) remain largely unknown. We carried out comparative transcriptome analyses between wetA null mutant and wild type (WT) asexual spores in three representative species spanning the diversity of the genus Aspergillus: the genetic model A. nidulans, the agricultural pest A. flavus, and the human pathogen A. fumigatus. We discovered that WetA regulates asexual sporulation in all three species via a negative feedback loop that represses BrlA, the cascade’s first step. Furthermore, ChIP-seq experiments in A. nidulans asexual spores suggest that WetA is a DNA-binding protein that interacts with a novel regulatory element, which we term the WetA Response Element (WRE). Interestingly, the WRE is found completely conserved in the non-coding region upstream of the wetA translation start site of many diverse Aspergillus genomes. In contrast, several global transcriptional regulators, most notably those in the velvet complex (veA, velB, and laeA) known to regulate the coupling between asexual development and production of secondary metabolites, show species-specific regulatory patterns. These results suggest that the BrlA-AbaA-WetA cascade’s regulatory role in cellular and chemical development of asexual spores is functionally conserved, but that the WetA-associated GRN has diverged during Aspergillus evolution. This entry is for the ChIP-seq data.
2018-07-24 | GSE114141 | GEO
Project description:In filamentous fungi, asexual sporulation involves morphological differentiation and metabolic changes. The process of asexual spore formation is tightly regulated by a variety of transcription factors including VosA, VelB, and WetA. A number of studies have demonstrated that these three transcription factors are key regulators of asexual spore formation and maturation in the model filamentous fungus Aspergillus nidulans. To gain a more mechanistic view of the roles these transcription factors play in asexual spores, genome-wide and metabolomic analyses were conducted in A. nidulans conidia. RNA sequencing and chromatin immunoprecipitation-based sequencing data suggested that the three transcription factors directly or indirectly regulate the expression of genes associated with spore-wall integrity, asexual development, and secondary metabolism. In addition, metabolomics analysis of conidia extracts showed strikingly different primary and secondary metabolite profiles for wild-type and mutant conidia. These results suggest that WetA, VosA, and VelB play key roles in the morphological development of and metabolic changes in conidia. This entry is for the RNA-seq data.
2021-01-11 | GSE154639 | GEO
Project description:In filamentous fungi, asexual sporulation involves morphological differentiation and metabolic changes. The process of asexual spore formation is tightly regulated by a variety of transcription factors including VosA, VelB, and WetA. A number of studies have demonstrated that these three transcription factors are key regulators of asexual spore formation and maturation in the model filamentous fungus Aspergillus nidulans. To gain a more mechanistic view of the roles these transcription factors play in asexual spores, genome-wide and metabolomic analyses were conducted in A. nidulans conidia. RNA sequencing and chromatin immunoprecipitation-based sequencing data suggested that the three transcription factors directly or indirectly regulate the expression of genes associated with spore-wall integrity, asexual development, and secondary metabolism. In addition, metabolomics analysis of conidia extracts showed strikingly different primary and secondary metabolite profiles for wild-type and mutant conidia. These results suggest that WetA, VosA, and VelB play key roles in the morphological development of and metabolic changes in conidia. This entry is for the ChIP-seq data.
2021-01-11 | GSE154630 | GEO
Project description:Fusarium graminearum (teleomorph Gibberella zeae) is a prominent pathogen that infects major cereal crops, such as wheat, barley, and maize. Conidiogenesis had been intensively studied in Aspergillus nidulans and regulatory pathway genes have been known to regulate conidiogenesis in stage specific manner. We reported the functional analyses of flbD, abaA, and wetA orthologs in F. graminearum. To understand genome-wide transcriptional profiling of conidiation, we employed RNA-seq of the wild-type Fusarium graminearum Z-3639 and each gene deletion mutants with three time courses (0 h, 6 h and 12 h after induction of conidiogenesis). AbaA experiment: 6 samples examined: 0 h, 6 h and 12 h after induction of conidiogenesis of Fusarium graminearum Z-3639 wild type and ΔabaA(ΔabaA::gen) mutant strains WetA experiment: 3 samples examined: 0 h, 6 h and 12 h after induction of conidiogenesis of Fusarium graminearum ΔwetA(ΔwetA::gen) mutant strains flbD experiment: 3 samples examined: 0 h, 6 h and 12 h after induction of conidiogenesis of Fusarium graminearum ΔflbD(ΔflbD::gen) mutant strains
2013-11-10 | E-GEOD-46133 | biostudies-arrayexpress
Project description:Mycotic leratitis is the corneal inflammation predominantly caused by Fusarium and Aspergillus species. Corneal epithelium is the earliest cell type encounter the invading pathogen. The innate immune responses of human corneal epithelial cells against Aspergillus flavus is not known. Here we studied the role of human corneal epithelial cells against Aspergillus flavus infection. The results showed that corneal epithelial cells internalized Aspergillus flavus conidia through actin mediated polymerization surrounding the conidia. Further the actin inhibitor cytochalasin D treatment reduced the formation actin ring around the conidia. The engulfed conidia acquired endosomal proteins as revealed by immunofluorescence analsyisis. Mass spectromtery of phagosomal proteins confirmed the recruitment of endosomal proteins and other proteins involved in phagocytosis. These results show the involvement of corneal epithelial cells in anti fungal defense.
2021-04-07 | PXD019512 | Pride
Project description:Human corneal epithelial cells internalize Aspergillus flavus conidia. But the biochemical response of corneal epithelial cells in response to A.flavus is not clear. In this study, NanoString analysis was used to study the immune genes expression in primary corneal epithelial cells and cell line infected with A. flavus conidia. The study revealed the differential expression of immune genes associated with TNF, Th17, NF-kB signaling and B cell receptor signaling in corneal epithelial cells. There is also difference in the response between cell line and primary cells to A. flavus implies the use of both cells to understand the host-pathogen interaction.
2021-06-01 | GSE175824 | GEO
Project description:Objective: Aspergillus flavus aflR, a gene encoding a Zn(II)2Cys6 DNA-binding domain, is an important transcriptional regulator of the aflatoxin biosynthesis gene cluster. Our previous results of GO analysis for the binding sites of AflR in A. flavus suggest that AflR may play an integrative regulatory role. This study aimed to investigate the integrative function of the aflR gene in A. flavus. Design: In this study, we used Aspergillus flavus NRRL3357 as a wild-type strain (WT) and constructed a knockout strain of A. flavus ΔaflR by homologous recombination. Based on the transcriptomics technology, we investigated the metabolic effects of aflR gene on growth, development and toxin synthesis of A. flavus, and discussed the overall regulation mechanism of aflR gene on A. flavus at the transcriptional level. Results: The disruption of aflR severely affected the aflatoxin biosynthetic pathway, resulting in a significant decrease in aflatoxin production. In addition, disrupted strains of the aflR gene produced relatively sparse conidia and a very small number of sclerotia. However, the biosynthesis of cyclopiazonic acid (CPA) was not affected by aflR gene disruption. Transcriptomic analysis of the ΔaflR strain grown on potato dextrose agar (PDA) plates at 0 h, 24 h, and 72 h showed that expression of clustering genes involved in the biosynthesis of aflatoxin was significantly down-regulated. Meanwhile, the ΔaflR strain showed significant expression differences in genes involved in spore germination, sclerotial development, and carbohydrate metabolism compared to the WT strain. Conclusions: The results showed that the A. flavus aflR gene also played a positive role in the growth and development of fungi.
2021-07-16 | GSE179978 | GEO
Project description:Fusarium graminearum (teleomorph Gibberella zeae) is a prominent pathogen that infects major cereal crops, such as wheat, barley, and maize. Conidiogenesis had been intensively studied in Aspergillus nidulans and regulatory pathway genes have been known to regulate conidiogenesis in stage specific manner. We reported the functional analyses of flbD, abaA, and wetA orthologs in F. graminearum. To understand genome-wide transcriptional profiling of conidiation, we employed RNA-seq of the wild-type Fusarium graminearum Z-3639 and each gene deletion mutants with three time courses (0 h, 6 h and 12 h after induction of conidiogenesis).
2013-11-10 | GSE46133 | GEO
Project description:Aspergillus flavus and A. parasiticus are two of the most important aflatoxin-producing species that contaminate agricultural commodities worldwide. Both species are heterothallic and undergo sexual reproduction in laboratory crosses. Here, we examine the possibility of interspecific matings between A. flavus and A. parasiticus. These species can be distinguished morphologically and genetically, as well as by their mycotoxin profiles. Aspergillus flavus produces both B aflatoxins and cyclopiazonic acid (CPA), B aflatoxins or CPA alone, or neither mycotoxin; Aspergillus parasiticus produces B and G aflatoxins or the aflatoxin precursor O-methylsterigmatocystin, but not CPA. Only four out of forty-five attempted interspecific crosses between compatible mating types of A. flavus and A. parasiticus were fertile and produced viable ascospores. Single ascospore strains from each cross were isolated and were shown to be recombinant hybrids using multilocus genotyping and array comparative genome hybridization. Conidia of parents and their hybrid progeny were haploid and predominantly monokaryons and dikaryons based on flow cytometry. Multilocus phylogenetic inference showed that experimental hybrid progeny were grouped with naturally occurring A. flavus L strain and A. parasiticus. Higher total aflatoxin concentrations in some F1 progeny strains compared to midpoint parent aflatoxin levels indicate synergism in aflatoxin production; moreover, three progeny strains synthesized G aflatoxins that were not produced by the parents, and there was evidence of putative allopolyploidization in one strain. These results suggest that hybridization is an important diversifying force resulting in the genesis of novel toxin profiles in these agriculturally important species.
2015-10-01 | GSE61981 | GEO