Cryptococcus neoformans
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ABSTRACT:
PROVIDER: PRJNA185599 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Using the yeast Cryptococcus neoformans, we describe a mechanism by which transposons are initially targeted for RNAi-mediated genome defense. We show that intron-containing mRNA precursors template siRNA synthesis. We identify a Spliceosome-Coupled And Nuclear RNAi (SCANR) complex required for siRNA synthesis and demonstrate that it physically associates with the spliceosome. We find that RNAi target transcripts are distinguished by suboptimal introns and abnormally high occupancy on spliceosomes. Functional investigations demonstrate that the stalling of mRNA precursors on spliceosomes is required for siRNA accumulation. Lariat debranching enzyme is also necessary for siRNA production, suggesting a requirement for processing of stalled splicing intermediates. We propose that recognition of mRNA precursors by the SCANR complex is in kinetic competition with splicing, thereby promoting siRNA production from transposon transcripts stalled on spliceosomes. Disparity in the strength of gene expression signals encoded by transposons versus genes offers an avenue for the evolution of genome defense.
2013-01-21 | GSE43363 | GEO
Project description:Using the yeast Cryptococcus neoformans, we describe a mechanism by which transposons are initially targeted for RNAi-mediated genome defense. We show that intron-containing mRNA precursors template siRNA synthesis. We identify a Spliceosome-Coupled And Nuclear RNAi (SCANR) complex required for siRNA synthesis and demonstrate that it physically associates with the spliceosome. We find that RNAi target transcripts are distinguished by suboptimal introns and abnormally high occupancy on spliceosomes. Functional investigations demonstrate that the stalling of mRNA precursors on spliceosomes is required for siRNA accumulation. Lariat debranching enzyme is also necessary for siRNA production, suggesting a requirement for processing of stalled splicing intermediates. We propose that recognition of mRNA precursors by the SCANR complex is in kinetic competition with splicing, thereby promoting siRNA production from transposon transcripts stalled on spliceosomes. Disparity in the strength of gene expression signals encoded by transposons versus genes offers an avenue for the evolution of genome defense. Small RNA profile of wild-type Cryptococcus neoformans was determined by deep sequencing using the Illumina SBS platform
2013-01-21 | E-GEOD-43363 | biostudies-arrayexpress
Project description:Light is a universal environmental signal perceived by many organisms, including the fungi in which light regulates both common and unique biological processes depending on the species. We conducted a whole-genome microarray analysis on the basidiomycete fungus Cryptococcus neoformans to identify light-regulated genes.
2010-04-23 | GSE21484 | GEO
Project description:The RNA interference (RNAi) mediated by homology-dependent degradation of the target mRNA with small RNA molecules plays a key role in controlling transcription and translation processes in a number of eukaryotic organisms. The RNAi machinery is also evolutionarily conserved in a wide variety of fungal species, including pathogenic fungi. To elucidate the physiological functions of the RNAi pathway in Cryptococcus neoformans that causes fungal meningitis, here we performed genetic analyses for genes encoding Argonaute (AGO1 and AGO2), RdRP (RDP1), and Dicers (DCR1 and DCR2) in both serotype A and D C. neoformans. The present study shows that Ago1, Rdp1, and Dcr2 are the major components of the RNAi process occurring in C. neoformans. However, the RNAi machinery is not involved in regulation of production of two virulence factors (capsule and melanin), sexual differentiation, and diverse stress response. To further gain insights into the global regulatory circuit governed by the RNAi pathway, comparative transcriptome analysis using the serotype A and D RNAi mutants was performed. Notably, an increase in transcript abundance of active transposons, such as T2 and T3, was observed in the rdp1Δ mutant. Therefore, this study can improve our understanding of the role of the RNAi genes in human fungal pathogens including C. neoformans. This SuperSeries is composed of the SubSeries listed below.
2010-05-01 | GSE21178 | GEO
Project description:Light is a universal environmental signal perceived by many organisms, including the fungi in which light regulates both common and unique biological processes depending on the species. We conducted a whole-genome microarray analysis on the basidiomycete fungus Cryptococcus neoformans to identify light-regulated genes. Two-condition experiment, cells grown in complete darkness or exposed to white light. Six biological replicates independently grown and harvested. One replicate per array.
2010-04-23 | E-GEOD-21484 | biostudies-arrayexpress
Project description:The RNA interference (RNAi) mediated by homology-dependent degradation of the target mRNA with small RNA molecules plays a key role in controlling transcription and translation processes in a number of eukaryotic organisms. The RNAi machinery is also evolutionarily conserved in a wide variety of fungal species, including pathogenic fungi. To elucidate the physiological functions of the RNAi pathway in Cryptococcus neoformans that causes fungal meningitis, here we performed genetic analyses for genes encoding Argonaute (AGO1 and AGO2), RdRP (RDP1), and Dicers (DCR1 and DCR2) in both serotype A and D C. neoformans. The present study shows that Ago1, Rdp1, and Dcr2 are the major components of the RNAi process occurring in C. neoformans. However, the RNAi machinery is not involved in regulation of production of two virulence factors (capsule and melanin), sexual differentiation, and diverse stress response. To further gain insights into the global regulatory circuit governed by the RNAi pathway, comparative transcriptome analysis using the serotype A and D RNAi mutants was performed. Notably, an increase in transcript abundance of active transposons, such as T2 and T3, was observed in the rdp1Δ mutant. Therefore, this study can improve our understanding of the role of the RNAi genes in human fungal pathogens including C. neoformans.
2010-05-01 | GSE21177 | GEO
Project description:The RNA interference (RNAi) mediated by homology-dependent degradation of the target mRNA with small RNA molecules plays a key role in controlling transcription and translation processes in a number of eukaryotic organisms. The RNAi machinery is also evolutionarily conserved in a wide variety of fungal species, including pathogenic fungi. To elucidate the physiological functions of the RNAi pathway in Cryptococcus neoformans that causes fungal meningitis, here we performed genetic analyses for genes encoding Argonaute (AGO1 and AGO2), RdRP (RDP1), and Dicers (DCR1 and DCR2) in both serotype A and D C. neoformans. The present study shows that Ago1, Rdp1, and Dcr2 are the major components of the RNAi process occurring in C. neoformans. However, the RNAi machinery is not involved in regulation of production of two virulence factors (capsule and melanin), sexual differentiation, and diverse stress response. To further gain insights into the global regulatory circuit governed by the RNAi pathway, comparative transcriptome analysis using the serotype A and D RNAi mutants was performed. Notably, an increase in transcript abundance of active transposons, such as T2 and T3, was observed in the rdp1Δ mutant. Therefore, this study can improve our understanding of the role of the RNAi genes in human fungal pathogens including C. neoformans.
2010-05-01 | GSE21176 | GEO
Project description:Rampant transposition following RNAi loss cause hypermutation and antifungal drug resistance in Cryptococcus neoformans
| PRJNA749953 | ENA
Project description:The RNA interference (RNAi) mediated by homology-dependent degradation of the target mRNA with small RNA molecules plays a key role in controlling transcription and translation processes in a number of eukaryotic organisms. The RNAi machinery is also evolutionarily conserved in a wide variety of fungal species, including pathogenic fungi. To elucidate the physiological functions of the RNAi pathway in Cryptococcus neoformans that causes fungal meningitis, here we performed genetic analyses for genes encoding Argonaute (AGO1 and AGO2), RdRP (RDP1), and Dicers (DCR1 and DCR2) in both serotype A and D C. neoformans. The present study shows that Ago1, Rdp1, and Dcr2 are the major components of the RNAi process occurring in C. neoformans. However, the RNAi machinery is not involved in regulation of production of two virulence factors (capsule and melanin), sexual differentiation, and diverse stress response. To further gain insights into the global regulatory circuit governed by the RNAi pathway, comparative transcriptome analysis using the serotype A and D RNAi mutants was performed. Notably, an increase in transcript abundance of active transposons, such as T2 and T3, was observed in the rdp1? mutant. Therefore, this study can improve our understanding of the role of the RNAi genes in human fungal pathogens including C. neoformans. This SuperSeries is composed of the following subset Series: GSE21176: Molecular and Functional Characterization of the role of RNA silencing components in Cryptococcus neoformans [RNAi_Serotype A] GSE21177: Molecular and Functional Characterization of the role of RNA silencing components in Cryptococcus neoformans [RNAi_Serotype D] Refer to individual Series
2010-05-01 | E-GEOD-21178 | biostudies-arrayexpress
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.
2009-09-04 | GSE17887 | GEO