Transcriptome analysis of cryptococcal IPK mutants
Ontology highlight
ABSTRACT:
ORGANISM(S): Cryptococcus neoformans var. grubii H99
PROVIDER: GSE78824 | GEO | 2016/03/03
SECONDARY ACCESSION(S): PRJNA314068
REPOSITORIES: GEO
Similar Datasets
Project description:In eukaryotes, inositol polyphosphates perform essential metabolic and signaling functions. Using human fungal pathogen Cryptococcus neoformans as a model, we created mutants in three inositol polyphosphates kinases: Arg1, Ipk1 and Kcs1. Each of the mutants produces a unique repertoire of inositol polyphosphates, different from the wild type strain. Comparative phenotypic and transcriptome analyses of wild type and mutant strains indicates that inositol polyphosphate PP-IP5 (IP7) is the key regulator of gene expression, fitness and virulence in C. neoformans. Comparison of WT and mutants (Darg1, Dkcs1 and Dipk1) grown in broth culture in the absence of stress.
2016-03-03 | E-GEOD-78824 | biostudies-arrayexpress
Project description:Cryptococcus neoformans is the most common cause of fungal meningitis, with high mortality and morbidity. The reason for the frequent occurrence of Cryptococcus infection in the central nervous system (CNS) is poorly understood. In this study, we find that inositol plays an important role in the transversal of Cryptococcus across the blood-brain barrier (BBB) both in an in vitro human BBB model and in vivo animal models. The inositol stimulation of BBB crossing is dependent upon fungal inositol transporters. The upregulation of genes involved in the inositol catabolism pathway is evident in a microarray analysis. The expression of CPS1, a gene encoding the hyaluronic acid synthase in Cryptococcus, is also upregulated by the inositol treatment. The production of hyaluronic acid increased in cells treated with inositol, which leads to the enhanced binding ability of Cryptococcus cells to the human brain microvascular endothelial cells (HBMECs) constituting the BBB. Overall, our studies provide a mechanism for inositol-dependent Cryptococcus transversal of the BBB, supporting our hypothesis that host inositol utilization by the fungus contributes to Cryptococcus CNS infection.
2012-09-29 | GSE41211 | GEO
Project description:Cryptococcus neoformans is the most common cause of fungal meningitis, with high mortality and morbidity. The reason for the frequent occurrence of Cryptococcus infection in the central nervous system (CNS) is poorly understood. In this study, we find that inositol plays an important role in the transversal of Cryptococcus across the blood-brain barrier (BBB) both in an in vitro human BBB model and in vivo animal models. The inositol stimulation of BBB crossing is dependent upon fungal inositol transporters. The upregulation of genes involved in the inositol catabolism pathway is evident in a microarray analysis. The expression of CPS1, a gene encoding the hyaluronic acid synthase in Cryptococcus, is also upregulated by the inositol treatment. The production of hyaluronic acid increased in cells treated with inositol, which leads to the enhanced binding ability of Cryptococcus cells to the human brain microvascular endothelial cells (HBMECs) constituting the BBB. Overall, our studies provide a mechanism for inositol-dependent Cryptococcus transversal of the BBB, supporting our hypothesis that host inositol utilization by the fungus contributes to Cryptococcus CNS infection. To understand the effect of inositol on gene expression profiles during cell development, microarray experiments were performed to monitor the genes regulated by inositol. H99 overnight culture was washed with dH2O once, and cells were inoculated on SD medium with or without inositol. Cells were collected from SD plates 24 hr post-inoculation, washed with dH2O, and total RNA was purified. Total RNAs were extracted using Trizol Reagents (Invitrogen) and purified using the Qiagen RNeasy cleanup kit (Qiagen). Cy3 and Cy5-labeled cDNA were generated by incorporating amino-allyl-dUTP during reverse transcription of 5 µg of total RNA as described previously and competitively hybridized to a JEC21 whole-genome array generated previously at Washington University in Saint Louis. After hybridization, arrays were scanned with a GenePix 4000B scanner (Axon Instruments, http://www.axon.com) and analyzed by using GenePix Pro version 4.0 and BRB array tools (developed by Richard Simon and Amy Peng Lam at the National Cancer Institute; http://linus.nci.nih.gov/BRB-ArrayTools.html)
2012-09-29 | E-GEOD-41211 | biostudies-arrayexpress
Project description:Cryptococcus neoformans is a fungal pathogen responsible for hundreds of thousands of deaths per year. Its critical virulence factor is a polysacharride capsule which grows large upon entry into a mammalian host. We previously identified USV101 as a transcription factor whose deletion results in enlarged capsules. Here, we characterize strains lacking or overexpressing USV101 in terms of their virulence-related phenotypes, the altered course of infection by them and immune response to them in a mouse model, the relationship of Usv101 to other transcription factors involved in capsule regulation, and the changes in Usv101 activity during capsule induction. To study the function of Usv101, a key C. neoformans regulator of virulence, and its interactions with downstream capsule-regulating TFs GAT201 and SP1, expression profiles were generated by RNA-seq of a usv101 deletion mutant, a USV101 overexpression mutant, strains expressing GAT201 under various promoters, various double mutants, and wildtype cells grown in a capsule non-inducing condition, a capsule inducing condition for 90 minutes, or a capsule inducing condition for 24 hours.
2016-03-31 | E-GEOD-69532 | biostudies-arrayexpress
Project description:The cAMP-pathway plays a central role in regulation of growth, differentiation, and virulence of human pathogenic fungi, including Cryptococcus neoformans. Three major upstream signaling regulators of the adenylyl cyclase (Cac1), Ras, Aca1 (Adenylyl cyclase-associated protein 1) and G-alpha subunit protein (Gpa1), have been identified to control the cAMP-pathway in C. neoformans, but their functional relationship remains elusive. Here we performed genome-wide transcriptome analysis with C. neoformans ras1, gpa1, cac1, aca1, and pka1 pka2 mutants by DNA microarray. The aca1, gpa1, cac1, and pka1 pka2 mutants displayed similar transcriptome patterns to each other whereas the ras1 mutant exhibited distinctive transcriptome patterns compared to WT and the cAMP mutants. Interestingly, a number of environmental stress response genes are differentially modulated in the ras1 and cAMP mutants. In fact, the Ras1-signaling pathway was found to be involved in osmotic and genotoxic stress response, and maintenance of cell wall integrity via the Cdc24-dependent signaling pathway. Through this microarray analysis, we have identified a number of cAMP-dependent genes, including GRE2, HSP12, ENA1, TCO2, PKP2, CAT1, in C. neoformans. Notably, a majority of ergosterol biosynthesis genes were found to be upregulated in the cAMP mutants. Interestingly, the gpa1, cac1, and pka1 mutants, but not the aca1 and pka2 mutants were hypersensitive to amphotericin B, but resistant to fluconazole. In conclusion, we demonstrated in this study that the Ras1- and cAMP-signaling pathways are involved in stress response and sterol biosynthesis of C. neoformans. There are more than 95% of genome homology between JEC21 and H99. Therefore 100 slides of JEC21 (cryptococcus neoformans var. neoformans serotype D) 70-mer oligo are used in this analysis, 3 biological replicate experiments are performed, total RNAs are extracted with 6 strains from H99 (H99 Wild type strain (Cryptococcus neoformans var. grubii serotype A), ras1Î, aca1Î, gpa1Î, cac1Î, pka1Îpka2Î), We use the mixed all of total RNAs from this experiment as a control RNA. We use Cy5 as Sample dye and Cy3 as a control dye. several sample are dye swaped.
2010-05-22 | E-GEOD-17338 | biostudies-arrayexpress
Project description:CircRNAs are a recently well-known regulator that mediates a variety of biological processes. Cryptococcus neoformans is an environmental fungal pathogen that can cause fatal cryptococcal meningitis in immunocompromised individuals. However, the involvement of circRNA in cryptococcal infection remains unclear. In this study, high‐throughput microarray was performed to identify the circRNA expression profile in cryptococcal meningitis patients.
2020-12-07 | GSE159601 | GEO
Project description:We compared the interaction between Cryptococcus gattii species complex strain R265 and Cryptococcus neoformans species complex strain H99, molecular type VNI, with murine macrophages to ascertain similarities and differences in their intracellular pathogenic strategy. Parameters analyzed include non-lytic exocytosis using time-lapse microscopy, phagolysosomal pH by dual fluorescent microscopy, intracellular capsular growth, phagolysosomal membrane permeabilization by flow cytometry, and the macrophage transcriptional response by gene expression microarray analysis. Using microarrays, we compared the transcriptional response of Bone Marrow-derived macrophages (BMDM) infected with C. gattii species complex strain R265 or C. neoformans species complex strain H99, relative to uninfected BMDM collected from the same time intervals, 2hr and 24 hr post-infection. For analysis following normalization and summarization steps, a 2-way Analysis of Variance (ANOVA) with linear contrasts for treatment (infection/strain) and time (2 h or 24 h) vs. Control (uninfected) was performed with outputs of P value, Fold Change, and Mean Ratio. A linear contrast of uninfected controls (24 h uninfected vs 2 h uninfected) was also performed to generate a ‘time only’ gene list. Cutoff criteria for filtering gene lists was significant P values (p<0.01) with fold changes greater that 2 or less than –2. Ten genes from the filtered gene lists were selected for validation by qPCR, with four housekeeping genes for normalization and comparison.
2018-06-30 | GSE112668 | GEO
Project description:A family of APSES transcription factor is known to be fungal-specific transcriptional regulators and play important roles in governing growth, differentiation, and virulence of diverse fungal pathogens. Yet none of APSES-like transcription factors have been identified and investigated in a basidiomycetous fungal pathogen, Cryptococcus neoformans. In the present study we discovered an APSES-like transcription factor, Msa1 (Mbp1/Swi4-like APSES protein 1), as one of novel flucytosine-responsive genes (total 194 genes) identified through comparative transcriptome analysis of C. neoformans hybrid sensor kinase mutants, tco1 and tco2 mutants, which displayed differential flucytosine-susceptibility. Supporting the microarray data, Northern blot and quantitative RT-PCR analysis confirmed that expression of MSA1 is rapidly induced in response to flucytosine in the wild-type strain, but not in the tco1 and tco2 mutants. Furthermore, C. neoformans with deletion of the MSA1 gene exhibited increased susceptibility to flucytosine. Intriguingly, Msa1 plays pleiotropic roles in diverse cellular process of C. neoformans. Msa1 positively regulates ergosterol biosynthesis and thereby its inhibition confers increased susceptibility and resistance to amphotericin B and azole drugs, respectively. Msa1 is also involved in DNA damage repair counteracting genotoxic stresses. During sexual differentiation Msa1 represses pheromone production, but promotes cell-cell fusion. Furthermore Msa1 is required for production of antioxidant melanin pigment and full virulence of C. neoformans. Finally we also performed DNA microarrray analysis to identify Msa1-regulated genes in C. neoformans. A majority of them were found to be involved in cell cycle regulation and DNA repair. Therefore, this study provides a novel antifungal therapeutic method for treatment of cryptococcosis. There are more than 95% of genome homology between JEC21 and H99. Therefore 24 slides of JEC21 (cryptococcus neoformans var. neoformans serotype D) 70-mer oligo are used in this analysis, 3 biological replicate experiments are performed, total RNAs are extracted under 2 conditions (with or without treatment of Flucytosine) with 4 strains from H99 (H99 Wild type strain (Cryptococcus neoformans var. grubii serotype A), tco1Δ , tco2Δ , skn7Δ), We use the mixed all of total RNAs from this experiment as a control RNA. We use Cy5 as Sample dye and Cy3 as a control dye.
2011-06-23 | E-GEOD-30154 | biostudies-arrayexpress
Project description:Ubiquitination is a reversible protein modification involved in various cellular processes in eukaryotic cells. Deubiquitinating enzymes, the proteins responsible for the removal of ubiquitin, act as essential regulators to maintain ubiquitin homeostasis and to exquisitely regulate protein degradation via the ubiquitination pathway. Cryptococcus neoformans is an important basidiomycete pathogen that causes life-threatening meningoencephalitis primarily within the immunocompromised population. In order to understand the possible influence deubiquitinating enzymes have on growth and virulence of the model pathogenic yeast Cryptococcus neoformans, we generated deletion mutants of 7 putative deubiquitinase genes. Compared to other deubiquitinating enzyme mutants, a ubp5M-bM-^HM-^F mutant exhibited severely attenuated virulence and many distinct phenotypes, including decreased capsule formation, hypomelanization, defective sporulation, and elevated sensitivity to several external stressors (such as high temperature, oxidative and nitrosative stresses, high salts, and antifungal agents). Ubp5 appears to be the major deubiquitinating enzyme in C. neoformans for maintaining a pool of free ubiquitin for stress responses, supports the evolutionary divergence of Cryptococcus sp. from the model yeast S. cerevisiae, and provides an important paradigm for understanding the potential role of deubiquitination in virulence by other pathogenic fungi. In addition, other putative deubiquitinase mutants (doa4M-bM-^HM-^F and ubp13M-bM-^HM-^F) exhibit similar phenotypes to the ubp5M-bM-^HM-^F mutant, illustrating possible functional overlap among deubiquitinating enzymes in C. neoformans. Certain functioning deubiquitinating enzymes are essential for the virulence composite of C. neoformans and provide an additional yeast survival and propagation advantage in the host. In this study, transcription profiles of ubp5 mutant and WT Cryptococcus neoformans strains were compared in a dye-swap experiment following 1hr exposure to either 30C or 37C.
2012-04-10 | E-GEOD-35067 | biostudies-arrayexpress
Project description:Cells respond to stress and starvation by adjusting their growth rate and enacting stress defense programs. In eukaryotes this involves inactivation of TORC1, which in turn triggers downregulation of ribosome and protein synthesis genes and upregulation of stress response genes. Here we report that the highly conserved inositol pyrophosphate second messengers (including 1-PP-IP5, 5-PP-IP4, and 5-PP-IP5) are also critical regulators of cell growth and the general stress response, acting in parallel to the TORC1 pathway to control the activity of the class I HDAC Rpd3L. In fact, yeast cells that cannot synthesize any of the PP-IPs mount little to no transcriptional response in osmotic, heat, or oxidative stress. Furthermore, PP-IP dependent regulation of Rpd3L occurs independently of the role individual PP-IPs (such as 5-PP-IP5) play in activating specialized stress/starvation response pathways. Thus, the PP-IP second messengers simultaneously activate and tune the global response to stress and starvation signals. 2-condition experiments. Includes the responses of wild-type (ACY 044) and mutant yeast strains (all are W303 background) to log growth and stress conditions. This series of microarrays were performed on null mutants of various genes in the inositol pyrophosphate synthesis pathway, including several members of the Rpd3L histone deacetylase complex. All mutants were made in W303 strain, MatA yeast, using standard techniques (homologous recombination). Several stress conditions were tested, including heat-shock, oxidative (H2O2), and osmotic stress (0.375M KCl). Cells in mid-log growth were subjected to stress for 20 minutes. In one instance the TOR inhibitor rapamycin was added to determine whether PP-IPs act above/at or below TORC1 in activating the ESR. Taken together, these microarrays show the role of the inositol pyrophosphate synthesis pathway in activating the ESR in stress.
2013-03-22 | E-GEOD-45370 | biostudies-arrayexpress