RNA-Seq and ChIP Seq analysis of the Cu metalloregulatory transcription factor Cuf1 in Cryptococcus neoformans in response to Cu availability
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ABSTRACT:
ORGANISM(S): Cryptococcus neoformans var. grubii H99
PROVIDER: GSE110122 | GEO | 2018/10/29
REPOSITORIES: GEO
Similar Datasets
Project description:The essential yet toxic nature of Cu ions in living cells requires exquisite control of Cu homeostasis. The fungal pathogen C. neoformans regulates Cu homeostasis for survival during a complex host colonization process. During pulmonary infection host innate immune cells use Cu in an attempt to toxify C. neoformans, which responds by activating expression of Cu detoxifying proteins. However, during brain colonization expression of the fungal Cu import machinery is activated and required for virulence. To achieve the genetic plasticity required for adaptation to a continuum of distinct Cu environments within the host, C. neoformans utilizes the Cu-responsive transcription factor, Cuf1. Cuf1 is unique as it senses and responds to both high and low Cu environments, activating different sets of genes dependent on environmental Cu status. Cells lacking Cuf1 are compromised for colonization of the lungs and brain, highlighting Cuf1 as an important virulence factor. A genome-wide assessment of the Cuf1 binding sites in the genome of C. neoformans driven by Cu status identified novel genes required for adaptation to high and low Cu environments. These genes and their regulation provide new insights with respect to adaptive responses to changes in host Cu availability and could reveal new targets for therapeutic intervention in cryptococcosis.
2018-10-29 | GSE110120 | GEO
Project description:ChIP Seq analysis of the Cu metalloregulatory transcription factor Cuf1 in Cryptococcus neoformans in response to Cu availability
| PRJNA432922 | ENA
Project description:This SuperSeries is composed of the SubSeries listed below.
2020-02-16 | GSE126314 | GEO
Project description:The Cryptococcus neoformans NRG1 gene was identified using gene microarrays to define putative transcription factor genes regulated by the cyclic AMP (cAMP) signal transduction pathway. Disruption of NRG1 results in delayed capsule formation and mating, two phenotypes that are directly controlled by cAMP signaling. Putative targets of the Nrg1 transcription factor were identified using a second genome microarray to define differences in the transcriptomes of the wild-type and nrg1 mutant strains. These experiments implicate Nrg1 in the transcriptional control of multiple genes involved in carbohydrate metabolism and substrate oxidation, as well as the UGD1 gene encoding a UDP-glucose dehydrogenase required for polysaccharide capsule production and cell wall integrity. In addition to being under transcriptional control of the cAMP pathway, Nrg1 contains a putative protein kinase A phosphorylation site; mutation of this motif results in reduced Nrg1 activity. Consistent with prior studies in hypocapsular mutants, the nrg1 mutant strain is attenuated in an animal model of disseminated cryptococcal disease.
| S-EPMC1489281 | biostudies-literature
Project description:RNA-Seq and ChIP Seq analysis of the Cu metalloregulatory transcription factor Cuf1 in Cryptococcus neoformans in response to Cu availability
| PRJNA432913 | ENA
Project description:Purpose: Defining the regulatory role of the transcription factors, Cir1 and HapX, in C. neoformans. Methods: Chromatin immunoprecipitation followed by high-throughput sequencing was performed using chromatin immunoprecipitated DNA from the strains Cir1-Flag and HapX-Flag grown in low- and high-iron condition. Results: Cir1 and HapX bind to the promoter region of the genes involved in iron acquisition and metabolism in C. neoformans.
2020-02-16 | GSE126312 | GEO
Project description:Cryptococcus neoformans is an opportunistic fungal pathogen whose pathogenic lifestyle is linked to its ability to cope with fluctuating levels of copper (Cu), an essential metal involved in multiple virulence mechanisms, within distinct host niches. During lethal cryptococcal meningitis in the brain, C. neoformans senses a Cu-deficient environment and is highly dependent on its ability to scavenge trace levels of Cu from its host and adapt to Cu scarcity to successfully colonize this niche. In this study, we demonstrate for this critical adaptation, the Cu-sensing transcription factor Cuf1 differentially regulates the expression of the SOD1 and SOD2 superoxide dismutases in novel ways. Genetic and transcriptional analysis reveals Cuf1 specifies 5'-truncations of the SOD1 and SOD2 mRNAs through specific binding to Cu responsive elements within their respective promoter regions. This results in Cuf1-dependent repression of the highly abundant SOD1 and simultaneously induces expression of two isoforms of SOD2, the canonical mitochondrial targeted isoform and a novel alternative cytosolic isoform, from a single alternative transcript produced specifically under Cu limitation. The generation of cytosolic Sod2 during Cu limitation is required to maintain cellular antioxidant defense against superoxide stress both in vitro and in vivo. Further, decoupling Cuf1 regulation of Sod2 localization compromises the ability of C. neoformans to colonize organs in murine models of cryptococcosis. Our results provide a link between transcription factor-mediated alteration of protein localization and cell proliferation under stress, which could impact tissue colonization by a fungal pathogen.
| S-EPMC7961099 | biostudies-literature
Project description:Cryptococcus neoformans causes life-threatening meningoencephalitis in humans, but its overall biological and pathogenic regulatory circuits remain elusive, particularly due to the presence of an evolutionarily divergent set of transcription factors (TFs). Here, we report the construction of a high-quality library of 322 signature-tagged gene-deletion strains for 155 putative TF genes previously predicted using the DNA-binding domain TF database, and examine their in vitro and in vivo phenotypic traits under 32 distinct growth conditions. At least one phenotypic trait is exhibited by 145 out of 155 TF mutants (93%) and ∼85% of them (132/155) are functionally characterized for the first time in this study. The genotypic and phenotypic data for each TF are available in the C. neoformans TF phenome database (http://tf.cryptococcus.org). In conclusion, our phenome-based functional analysis of the C. neoformans TF mutant library provides key insights into transcriptional networks of basidiomycetous fungi and human fungal pathogens.
| S-EPMC4391232 | biostudies-literature
Project description:Chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) allows researchers to determine the genome-wide binding locations of individual transcription factors (TFs) at high resolution. This information can be interrogated to study various aspects of TF behaviour, including the mechanisms that control TF binding. Physical interaction between TFs comprises one important aspect of TF binding in eukaryotes, mediating tissue-specific gene expression. We have developed an algorithm, spaced motif analysis (SpaMo), which is able to infer physical interactions between the given TF and TFs bound at neighbouring sites at the DNA interface. The algorithm predicts TF interactions in half of the ChIP-seq data sets we test, with the majority of these predictions supported by direct evidence from the literature or evidence of homodimerization. High resolution motif spacing information obtained by this method can facilitate an improved understanding of individual TF complex structures. SpaMo can assist researchers in extracting maximum information relating to binding mechanisms from their TF ChIP-seq data. SpaMo is available for download and interactive use as part of the MEME Suite (http://meme.nbcr.net).
| S-EPMC3159476 | biostudies-literature
Project description:ChIP seq is a widely used assay to measure genome-wide protein binding. The decrease in costs associated with sequencing has led to a rise in the number of studies that investigate protein binding across treatment conditions or cell lines. In addition to the identification of binding sites, new studies evaluate the variation in protein binding between conditions. A number of approaches to study differential transcription factor binding have recently been developed. Several of these methods build upon established methods from RNA-seq to quantify differences in read counts. We compare how these new approaches perform on different data sets from the ENCODE project to illustrate the impact of data processing pipelines under different study designs. The performance of normalization methods for differential ChIP-seq depends strongly on the variation in total amount of protein bound between conditions, with total read count outperforming effective library size, or variants thereof, when a large variation in binding was studied. Use of input subtraction to correct for non-specific binding showed a relatively modest impact on the number of differential peaks found and the fold change accuracy to biological validation, however a larger impact might be expected for samples with more extreme copy number variations between them. Still, it did identify a small subset of novel differential regions while excluding some differential peaks in regions with high background signal. These results highlight proper scaling for between-sample data normalization as critical for differential transcription factor binding analysis and suggest bioinformaticians need to know about the variation in level of total protein binding between conditions to select the best analysis method. At the same time, validation using fold-change estimates from qRT-PCR suggests there is still room for further method improvement.
| S-EPMC4413818 | biostudies-literature