Project description:Fungi exhibit a large variety of morphological forms. Here, we examine the functions of a deeply conserved regulator of morphology in three fungal species: Saccharomyces cerevisiae, Candida albicans, and Histoplasma capsulatum. We show that, despite an estimated 600 million years since those species diverged from a common ancestor, Wor1 in C. albicans, Ryp1 in H. capsulatum, and Mit1 in S. cerevisiae are transcriptional regulators that recognize the same DNA sequence. Previous work established that Wor1 regulates white-opaque switching in C. albicans and that its ortholog Ryp1 regulates the yeast to mycelial transition in H. capsulatum. Here we show that the ortholog Mit1 in S. cerevisiae is also a master regulator of a morphological transition, in this case pseudohyphal growth. Full-genome chromatin immunoprecipitation experiments show that Mit1 binds to the control regions of the previously known regulators of pseudohyphal growth as well as those of many additional genes. Through a comparison of binding sites for Mit1 in S. cerevisiae, Wor1 in C. albicans, and Wor1 ectopically expressed in S. cerevisiae, we conclude that the genes controlled by the orthologous regulators overlap only slightly between these two species despite the fact that the DNA binding specificity of the regulators has remained largely unchanged. We suggest that the ancestral Wor1/Mit1/Ryp1 protein controlled aspects of cell morphology and that movement of genes in and out of the Wor1/Mit1/Ryp1 regulon is responsible, in part, for the differences of morphological forms among these species.
Project description:This SuperSeries is composed of the following subset Series: GSE32550: A conserved transcriptional regulator governs fungal morphology in widely diverged species [expression data] GSE32557: A conserved transcriptional regulator governs fungal morphology in widely diverged species [ChIP-chip, Transcriptional regulation by Mit1 and orthologs] Refer to individual Series
Project description:In this paper, we examine orthologs of a transcriptional regulator in three fungal species, Saccharomyces cerevisiae, Candida albicans, and Histoplasma capsulatum. We show that, despite an estimated 600 million years since those species diverged from a common ancestor, Wor1 in C. albicans, Ryp1 in H. capsulatum, and Mit1 in S. cerevisiae recognize the same DNA motif. Previous work established that Wor1 regulates white-opaque switching in C. albicans and that its ortholog Ryp1 regulates the yeast to mycelial transition in H. capsulatum. Here we show that the ortholog Mit1 in S. cerevisiae also regulates a morphological transition, in this case pseudohyphal growth. Full genome chromatin immunoprecipitation experiments show that Mit1 binds to the control regions of approximately 94 genes including the previously known regulators of pseudohyphal growth. Through a comparison of full genome chromatin immunoprecipitation experiments for Mit1 in S. cerevisiae, Wor1 in C. albicans, and Wor1 ectopically expressed in S. cerevisiae, we conclude that genes controlled by the orthologous regulators overlap only slightly between these two species. We suggest that the ancestral Wor1/Mit1/Ryp1 protein controlled aspects of cell morphology and that evolutionary movement of genes in and out of the Wor1/Mit1/Ryp1 regulon is responsible, in part, for the differences of morphological forms among these species. Consistent with this idea, ectopic expression of C. albicans Wor1 or H. capsulatum Ryp1 can drive the pseudohyphal growth program in S. cerevisiae. Replicate experiments for each of four strains compared with reference sample - WT, a Mit1 deletion haploid A strain, a Yhr177w deletion haploid A strain, and a double deletion haploid A strain. All were in the sigma 2000 background.
Project description:In this paper, we examine orthologs of a transcriptional regulator in three fungal species, Saccharomyces cerevisiae, Candida albicans, and Histoplasma capsulatum. We show that, despite an estimated 600 million years since those species diverged from a common ancestor, Wor1 in C. albicans, Ryp1 in H. capsulatum, and Mit1 in S. cerevisiae recognize the same DNA motif. Previous work established that Wor1 regulates white-opaque switching in C. albicans and that its ortholog Ryp1 regulates the yeast to mycelial transition in H. capsulatum. Here we show that the ortholog Mit1 in S. cerevisiae also regulates a morphological transition, in this case pseudohyphal growth. Full genome chromatin immunoprecipitation experiments show that Mit1 binds to the control regions of approximately 94 genes including the previously known regulators of pseudohyphal growth. Through a comparison of full genome chromatin immunoprecipitation experiments for Mit1 in S. cerevisiae, Wor1 in C. albicans, and Wor1 ectopically expressed in S. cerevisiae, we conclude that genes controlled by the orthologous regulators overlap only slightly between these two species. We suggest that the ancestral Wor1/Mit1/Ryp1 protein controlled aspects of cell morphology and that evolutionary movement of genes in and out of the Wor1/Mit1/Ryp1 regulon is responsible, in part, for the differences of morphological forms among these species. Consistent with this idea, ectopic expression of C. albicans Wor1 or H. capsulatum Ryp1 can drive the pseudohyphal growth program in S. cerevisiae.
Project description:In this paper, we examine orthologs of a transcriptional regulator in three fungal species, Saccharomyces cerevisiae, Candida albicans, and Histoplasma capsulatum. We show that, despite an estimated 600 million years since those species diverged from a common ancestor, Wor1 in C. albicans, Ryp1 in H. capsulatum, and Mit1 in S. cerevisiae recognize the same DNA motif. Previous work established that Wor1 regulates white-opaque switching in C. albicans and that its ortholog Ryp1 regulates the yeast to mycelial transition in H. capsulatum. Here we show that the ortholog Mit1 in S. cerevisiae also regulates a morphological transition, in this case pseudohyphal growth. Full genome chromatin immunoprecipitation experiments show that Mit1 binds to the control regions of approximately 94 genes including the previously known regulators of pseudohyphal growth. Through a comparison of full genome chromatin immunoprecipitation experiments for Mit1 in S. cerevisiae, Wor1 in C. albicans, and Wor1 ectopically expressed in S. cerevisiae, we conclude that genes controlled by the orthologous regulators overlap only slightly between these two species. We suggest that the ancestral Wor1/Mit1/Ryp1 protein controlled aspects of cell morphology and that evolutionary movement of genes in and out of the Wor1/Mit1/Ryp1 regulon is responsible, in part, for the differences of morphological forms among these species. Consistent with this idea, ectopic expression of C. albicans Wor1 or H. capsulatum Ryp1 can drive the pseudohyphal growth program in S. cerevisiae. IP strains were compared to untagged or deletion control strains
Project description:In this paper, we examine orthologs of a transcriptional regulator in three fungal species, Saccharomyces cerevisiae, Candida albicans, and Histoplasma capsulatum. We show that, despite an estimated 600 million years since those species diverged from a common ancestor, Wor1 in C. albicans, Ryp1 in H. capsulatum, and Mit1 in S. cerevisiae recognize the same DNA motif. Previous work established that Wor1 regulates white-opaque switching in C. albicans and that its ortholog Ryp1 regulates the yeast to mycelial transition in H. capsulatum. Here we show that the ortholog Mit1 in S. cerevisiae also regulates a morphological transition, in this case pseudohyphal growth. Full genome chromatin immunoprecipitation experiments show that Mit1 binds to the control regions of approximately 94 genes including the previously known regulators of pseudohyphal growth. Through a comparison of full genome chromatin immunoprecipitation experiments for Mit1 in S. cerevisiae, Wor1 in C. albicans, and Wor1 ectopically expressed in S. cerevisiae, we conclude that genes controlled by the orthologous regulators overlap only slightly between these two species. We suggest that the ancestral Wor1/Mit1/Ryp1 protein controlled aspects of cell morphology and that evolutionary movement of genes in and out of the Wor1/Mit1/Ryp1 regulon is responsible, in part, for the differences of morphological forms among these species. Consistent with this idea, ectopic expression of C. albicans Wor1 or H. capsulatum Ryp1 can drive the pseudohyphal growth program in S. cerevisiae.
Project description:Aspergillus fumigatus is the leading cause of invasive aspergillosis, which in immunocompromised patients results in a mortality rate as high as 90%. Earlier studies showed that HbxA is a global regulator in Aspergillus flavus affecting morphological development and secondary metabolism. Here, we determined its role in A. fumigatus, examining whether HbxA influences the regulation of asexual development, natural product biosynthesis, and virulence of this fungus. Our analysis demonstrated that removal of the hbxA gene caused a near-complete loss of conidial production in the mutant strain, as well as a slight reduction in colony growth. Other aspects of asexual development are affected, such as size and germination of conidia. Furthermore, we showed that in A. fumigatus, the loss of hbxA decreased the expression of the brlA central regulatory pathway involved in asexual development, as well as the expression of the "fluffy" genes flbB, flbD, and fluG HbxA was also found to regulate secondary metabolism, affecting the biosynthesis of multiple natural products, including fumigaclavines, fumiquinazolines, and chaetominine. In addition, using a neutropenic mouse infection model, hbxA was found to negatively impact the virulence of A. fumigatusIMPORTANCE The number of immunodepressed individuals is increasing, mainly due to the greater life expectancy in immunodepressed patients due to improvements in modern medical treatments. However, this population group is highly susceptible to invasive aspergillosis. This devastating illness, mainly caused by the fungus Aspergillus fumigatus, is associated with mortality rates reaching 90%. Treatment options for this disease are currently limited, and a better understanding of A. fumigatus genetic regulatory mechanisms is paramount for the design of new strategies to prevent or combat this infection. Our work provides new insight into the regulation of the development, metabolism, and virulence of this important opportunistic pathogen. The transcriptional regulatory gene hbxA has a profound effect on A. fumigatus biology, governing multiple aspects of conidial development. This is relevant since conidia are the main source of inoculum in Aspergillus infections. Importantly, hbxA also regulates the biosynthesis of secondary metabolites and the pathogenicity of this fungus.
Project description:The STORR gene fusion event is considered essential for the evolution of the promorphinan/morphinan subclass of benzylisoquinoline alkaloids (BIAs) in opium poppy as the resulting bi-modular protein performs the isomerization of (S)- to (R)-reticuline essential for their biosynthesis. Here, we show that of the 12 Papaver species analysed those containing the STORR gene fusion also contain promorphinans/morphinans with one important exception. P. californicum encodes a functionally conserved STORR but does not produce promorphinans/morphinans. We also show that the gene fusion event occurred only once, between 16.8-24.1 million years ago before the separation of P. californicum from other Clade 2 Papaver species. The most abundant BIA in P. californicum is (R)-glaucine, a member of the aporphine subclass of BIAs, raising the possibility that STORR, once evolved, contributes to the biosynthesis of more than just the promorphinan/morphinan subclass of BIAs in the Papaveraceae.
Project description:BackgroundCell wall integrity (CWI) is crucial for fungal growth, pathogenesis, and adaptation to extracellular environments. Calcofluor white (CFW) is a cell wall perturbant that inhibits fungal growth, yet little is known about how phytopathogenic fungi respond to the CFW-induced stress.ResultsIn this study, we unveiled a significant discovery that CFW triggered the translocation of the transcription factor CgCrzA from the cytoplasm to the nucleus in Colletotrichum gloeosporioides. This translocation was regulated by an interacting protein, CgMkk1, a mitogen-activated protein kinase involved in the CWI pathway. Further analysis revealed that CgMkk1 facilitated nuclear translocation by phosphorylating CgCrzA at the Ser280 residue. Using chromatin immunoprecipitation sequencing, we identified two downstream targets of CgCrzA, namely CgCHS5 and CgCHS6, which are critical for growth, cell wall integrity, and pathogenicity as chitin synthase genes.ConclusionsThese findings provide a novel insight into the regulatory mechanism of CgMkk1-CgCrzA-CgChs5/6, which enables response of the cell wall inhibitor CFW and facilitates infectious growth for C. gloeosporioides.