Extension of O-linked mannosylation in the Golgi is critical for cell wall integrity signaling and interaction with host cells in Cryptococcus neoformans pathogenesis
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA817221 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR18360400_1.fastq.gz | Fastqsanger.gz | |||
| SRR18360400_2.fastq.gz | Fastqsanger.gz | |||
| SRR18360401_1.fastq.gz | Fastqsanger.gz | |||
| SRR18360401_2.fastq.gz | Fastqsanger.gz | |||
| SRR18360402_1.fastq.gz | Fastqsanger.gz |
Items per page: 5 1 - 5 of 16 |
Similar Datasets
Project description:Purpose: To identify the downstream gene sets regulated by Mpk1p in C. neoformans normal and Tunicamycin-treated conditions, we compared the RNA-seq based transcriptional profiles. Methods: Total RNA was isolated according to the RNeasy Mini Kit (Qiagen) and all procedure for RNA sequencing were conducted by ebiogen. The mRNA was isolated by using the Poly(A) RNA Selection Kit (LEXOGEN) and isolated mRNAs were used for the cDNA synthesis. Results: Transcriptome analysis of the wild-type strain revealed that tunicamycin significantly increased expression of a subset of calcineurin-Crz1 pathway related genes , but most of which were not upregulated in O-glycan mutant strain. Conclusion: Our results support the essential role of O-glycan in maintaining cell wall integrity upon stress conditions of C. neoformans.
2022-11-11 | GSE198875 | GEO
Project description:Cryptococcus neoformans is a fungal pathogen of immunocompromised people that causes fatal meningitis. The fungal cell wall is essential to viability and pathogenesis of C. neoformans, and biosynthesis and repair of the wall is primarily controlled by the cell wall integrity (CWI) signaling pathway. Previous work by us and others have shown that deletion of genes encoding the four major kinases in the CWI signaling pathway, namely PKC1, BCK1, MKK2 and MPK1 results in severe cell wall phenotypes, sensitivity to a variety of cell wall stressors and, for Mpk1, reduced virulence in a mouse model. Here, we examined the global transcriptional response of gene deletions of BCK1, MKK2 and MPK1 compared to wild-type cells. We found over 1000 genes were differentially expressed in one or more of the deletion strains, with 115 genes differentially expressed in all three strains, many of which have been identified as genes regulated by the cAMP/protein kinase A (PKA) pathway. Biochemical measurements of cAMP levels in the kinase deletion stains revealed significantly less cAMP in all of the deletion strains compared to wild-type cells. The deletion strains also produced significantly smaller capsules than wild type KN99 under capsule inducing conditions, although they shed similar levels of capsule as wild type. Finally, addition of exogenous cAMP led to reduced sensitivity to cell wall stress and restored surface capsule to near wild-type levels. Thus, we have direct evidence of cross talk between the CWI and cAMP/PKA pathways that may have important implications for regulation of cell wall and capsule homeostasis. Comparison of three gene deletion strains to wild-type, with 3 biological replicates for each sample.
2014-07-01 | E-GEOD-57217 | biostudies-arrayexpress
Project description:Cryptococcus neoformans is a fungal pathogen of immunocompromised people that causes fatal meningitis. The fungal cell wall is essential to viability and pathogenesis of C. neoformans, and biosynthesis and repair of the wall is primarily controlled by the cell wall integrity (CWI) signaling pathway. Previous work by us and others have shown that deletion of genes encoding the four major kinases in the CWI signaling pathway, namely PKC1, BCK1, MKK2 and MPK1 results in severe cell wall phenotypes, sensitivity to a variety of cell wall stressors and, for Mpk1, reduced virulence in a mouse model. Here, we examined the global transcriptional response of gene deletions of BCK1, MKK2 and MPK1 compared to wild-type cells. We found over 1000 genes were differentially expressed in one or more of the deletion strains, with 115 genes differentially expressed in all three strains, many of which have been identified as genes regulated by the cAMP/protein kinase A (PKA) pathway. Biochemical measurements of cAMP levels in the kinase deletion stains revealed significantly less cAMP in all of the deletion strains compared to wild-type cells. The deletion strains also produced significantly smaller capsules than wild type KN99 under capsule inducing conditions, although they shed similar levels of capsule as wild type. Finally, addition of exogenous cAMP led to reduced sensitivity to cell wall stress and restored surface capsule to near wild-type levels. Thus, we have direct evidence of cross talk between the CWI and cAMP/PKA pathways that may have important implications for regulation of cell wall and capsule homeostasis.
2014-07-01 | GSE57217 | GEO
Project description:Chitin is an important fungal cell wall component that is cross-linked to β-glucan for structural integrity. Acquisition of chitin to glucan cross-links has previously been shown to be performed by transglycosylation enzymes in S. cerevisiae, called Congo Red hypersensitive (Crh) enzymes. Here, we characterized the impact of deleting all seven gene members of the crh gene family (crhA-G) in Aspergillus niger on cell wall integrity, cell wall composition and genome-wide gene expression. In this study, we show that the seven-fold knockout strain shows slightly compact plate growth, but no increased sensitivity to cell wall perturbing compounds. Additionally, we found that the cell wall composition of this knockout strain was virtually identical to that of the wild type. In congruence with these data, genome-wide expression analysis revealed very limited changes in gene expression and no signs of activation of the cell wall integrity response pathway. However, deleting the entire crh gene family in cell wall mutants that are deficient in either galactofuranose (ΔugmA) or α-glucan (ΔagsE and ΔagsA, ΔagsE), resulted in a synthetic growth defect and an increased sensitivity towards Congo Red compared the parental strains. Altogether, these results indicate that loss of the crh gene family in A. niger does not trigger the cell wall integrity response in itself, but does play an important role in ensuring cell wall integrity in mutant strains with reduced galactofuranose or α-glucan.
2019-12-21 | GSE142461 | GEO
Project description:Plant cell walls maintain their functional integrity during growth, defense and turgor generation through a dedicated cell wall integrity (CWI) maintenance mechanism. Upon detection of integrity impairment due to cell wall damage (CWD) compensatory responses are activated to maintain CWI. Responses include production of salicylic acid (SA), jasmonic acid (JA) and lignin as well as growth inhibition. Here we investigated the processes responsible for inducing growth inhibition upon CWD in Arabidopsis thaliana seedlings. Genetic studies implicated NITRATE REDUCTASE1 2 (NIA1 2) in the response to CWD. RNAseq-based transcriptomics showed that nearly all the CWD-induced transcript changes detectable in Col-0 were absent in nia1 2 seedlings.
2018-01-25 | GSE109613 | GEO
Project description:The cell wall is essential for viability of fungi and is an effective drug target in pathogens such as Candida albicans. The contribution of posttranscriptional gene regulators to cell wall integrity in C. albicans is unknown. We show that the C. albicans Ccr4-Pop2 mRNA deadenylase, a regulator of mRNA stability and translation, is required for cell wall integrity. The ccr4/pop2 mutants display reduced wall β-glucans and sensitivity to the echinocandin caspofungin. Moreover, the deadenylase mutants are compromised for filamentation and virulence. We demonstrate that defective cell walls in the ccr4/pop2 mutants are linked to dysfunctional mitochondria and phospholipid imbalance. To further understand mitochondrial function in cell wall integrity, we screened a Saccharomyces cerevisiae collection of mitochondrial mutants. We identify several mitochondrial proteins required for caspofungin tolerance and find a connection between mitochondrial phospholipid homeostasis and caspofungin sensitivity. We focus on the mitochondrial outer membrane SAM complex subunit Sam37, demonstrating it is required for both trafficking of phospholipids between the ER and mitochondria and cell wall integrity. Moreover, in C. albicans also Sam37 is essential for caspofungin tolerance. Our study provides the basis for an integrative view of mitochondrial function in fungal cell wall biogenesis and resistance to echinocandin antifungal drugs. Two-color experimental design comparing cells with a double-knockout of the CCR4 genes to cells with a reintegrated CCR4 gene.
2010-12-10 | E-GEOD-25891 | biostudies-arrayexpress
Project description:The human-pathogenic yeast Cryptococcus neoformans assembles two types of O-linked glycans on its proteins. In this study, we identified and functionally characterized the C. neoformans CAP6 gene, encoding an α1,3-mannosyltransferase responsible for the second mannose addition to minor O-glycans containing xylose in the Golgi apparatus. Two cell surface sensor proteins, Wml1 (WSC/Mid2-like) and Wml2, were found to be independent substrates of Cap6-mediated minor or Ktr3-mediated major O-mannosylation, respectively. The double deletion of KTR3 and CAP6 (ktr3Δ cap6Δ) completely blocked the mannose addition at the second position of O-glycans, resulting in the accumulation of proteins with O-glycans carrying only a single mannose. Tunicamycin (TM)-induced phosphorylation of the Mpk1 mitogen-activated protein kinase (MAPK) was greatly decreased in both ktr3Δ cap6Δ and wml1Δ wml2Δ strains. Transcriptome profiling of the ktr3Δ cap6Δ strain upon TM treatment revealed decreased expression of genes involved in the Mpk1-dependent cell wall integrity (CWI) pathway. Consistent with its defective growth under several stress conditions, the ktr3Δ cap6Δ strain was avirulent in a mouse model of cryptococcosis. Associated with this virulence defect, the ktr3Δ cap6Δ strain showed decreased adhesion to lung epithelial cells, decreased proliferation within macrophages, and reduced transcytosis of the blood-brain barrier (BBB). Notably, the ktr3Δ cap6Δ strain showed reduced induction of the host immune response and defective trafficking of ergosterol, an immunoreactive fungal molecule. In conclusion, O-glycan extension in the Golgi apparatus plays critical roles in various pathobiological processes, such as CWI signaling and stress resistance and interaction with host cells in C. neoformans. IMPORTANCE Cryptococcus neoformans assembles two types of O-linked glycans on its surface proteins, the more abundant major O-glycans that do not contain xylose residues and minor O-glycans containing xylose. Here, we demonstrate the role of the Cap6 α1,3-mannosyltransferase in the synthesis of minor O-glycans. Previously proposed to be involved in capsule biosynthesis, Cap6 works with the related Ktr3 α1,2-mannosyltransferase to synthesize O-glycans on their target proteins. We also identified two novel C. neoformans stress sensors that require Ktr3- and Cap6-mediated posttranslational modification for full function. Accordingly, the ktr3Δ cap6Δ double O-glycan mutant strain displays defects in stress signaling pathways, CWI, and ergosterol trafficking. Furthermore, the ktr3Δ cap6Δ strain is completely avirulent in a mouse infection model. Together, these results demonstrate critical roles for O-glycosylation in fungal pathogenesis. As there are no human homologs for Cap6 or Ktr3, these fungus-specific mannosyltransferases are novel targets for antifungal therapy.
| S-EPMC9765558 | biostudies-literature
Project description:A phosphoproteomic evaluation of the cellular response to micafungin (cell wall perturbant) in the filamentous fungi, A. nidulans, reveals putative, currently unknown cell wall integrity signaling (CWIS) associated proteins. This study used thirteen timepoints were taken from 0 to 10 minutes after cell wall exposure with two biological and two technical replicates. All data was processed using label free quantification with MaxQuant software.
2020-07-16 | PXD015038 | Pride
Project description:The cell wall is essential for viability of fungi and is an effective drug target in pathogens such as Candida albicans. The contribution of posttranscriptional gene regulators to cell wall integrity in C. albicans is unknown. We show that the C. albicans Ccr4-Pop2 mRNA deadenylase, a regulator of mRNA stability and translation, is required for cell wall integrity. The ccr4/pop2 mutants display reduced wall β-glucans and sensitivity to the echinocandin caspofungin. Moreover, the deadenylase mutants are compromised for filamentation and virulence. We demonstrate that defective cell walls in the ccr4/pop2 mutants are linked to dysfunctional mitochondria and phospholipid imbalance. To further understand mitochondrial function in cell wall integrity, we screened a Saccharomyces cerevisiae collection of mitochondrial mutants. We identify several mitochondrial proteins required for caspofungin tolerance and find a connection between mitochondrial phospholipid homeostasis and caspofungin sensitivity. We focus on the mitochondrial outer membrane SAM complex subunit Sam37, demonstrating it is required for both trafficking of phospholipids between the ER and mitochondria and cell wall integrity. Moreover, in C. albicans also Sam37 is essential for caspofungin tolerance. Our study provides the basis for an integrative view of mitochondrial function in fungal cell wall biogenesis and resistance to echinocandin antifungal drugs.
2010-12-10 | GSE25891 | GEO
Project description:Plant cells are surrounded by walls, which must often meet opposing functional requirements during plant growth and defense. The cells meet them by modifying wall structure and composition in a tightly controlled and adaptive manner. The modifications seem to be mediated by a dedicated cell wall integrity (CWI) maintenance mechanism. Currently the mode of action of the mechanism is not understood and it is unclear how its activity is coordinated with established plant defense signaling. We investigated both the responses to cell wall damage (CWD) compromising CWI and the underlying mechanism in Arabidopsis thaliana. A cellulose biosynthesis inhibitor isoxaben was used as a tool to induce the loss of cell wall integrity. Isoxaben was chosen because it only affects a certain cell type / differentiation stage, and weakens the cell walls indirectly by inhibiting a biosynthetic process, making CWD occurrence dependent on high turgor levels (allowing simultaneous manipulation of the responses by addition of osmotica like sorbitol, mannitol, etc.). Isoxaben treatment causes structural damage, induction of lesion formation, cell death, deposition of lignin and callose as well as production of jasmonic acid and salicylic acid. Isoxaben-resistant mutant ixr1-1 is included to ensure the specificity of the treatment.
2018-01-11 | GSE108987 | GEO