Project description:Wild type, ccr4∆, ccr4∆ pbp1∆ cells were grown in YPD medium from log phase to stationary phase. Total RNAs ere extracted and subjected to microarray analysis.
Project description:We report gene expression profiling in the fission yeast Schizosaccharomyces pombe. We performed high-throughput sequencing of RNA isolated from wild-type, erh1∆, and ccr4∆ strains. We find that many meiotic gene containing degradation sequence DSR are expressed in vegetative erh1∆, while these meiotic mRNAs do not increase in ccr4∆, indicating that Erh1 and Ccr4 target different set of genes during vegetative growth.
Project description:We report gene expression profiling in the fission yeast Schizosaccharomyces pombe. We performed high-throughput sequencing of RNA isolated from wild-type, clr6-1, ago1∆, red1∆, rrp6∆, clr4∆, ccr4∆, ccr4∆fep1, wild-type cells treated with an iron chelator (2,2′-bipyridyl; DIP) grown at 30°C or 18°C and ccr4∆fep1 cells treated with DIP at 18C. We find that many stress response genes, transmembrane transporters, and non-coding RNAs are up-regulated in cells cultured at 18°C. Our analyses concluded that Clr4 and Ccr4 are important for controlling transcript levels at 18°C and uncovered a role for iron homeostasis in adaptive genome control.
Project description:Pbp1 (polyA-binding protein - binding protein 1) is a stress granule marker and polyglutamine expansions in its mammalian ortholog ataxin-2 have been linked to neurodegenerative conditions. Pbp1 was recently shown to form intracellular assemblies that function in the negative regulation of TORC1 signaling under respiratory conditions. Furthermore, it was observed that loss of Pbp1 leads to mitochondrial dysfunction. Here, we show that loss of Pbp1 leads to a specific decrease in mitochondrial proteins whose encoding mRNAs are targets of the RNA-binding protein Puf3, suggesting a functional relationship between Pbp1 and Puf3. We found that Pbp1 stabilizes and promotes the translation of Puf3-target mRNAs in respiratory conditions, such as those involved in the assembly of cytochrome c oxidase. We further show that Pbp1 and Puf3 associate through their respective low complexity domains, which is required for target mRNA stabilization and translation. Our findings reveal a key role for Pbp1-containing assemblies in enabling the translation of mRNAs critical for mitochondrial biogenesis and respiration under metabolically challenging conditions. They may further explain prior associations of Pbp1/ataxin-2 with stress granule biology and RNA metabolism.
Project description:The yeast protein PBP1 has been implicated in diverse pathways such as polyadenylation, translation, RNA-DNA hybrid formation, stress granule homeostasis, mitochondrial dysfunction, and TORC1 sequestration. Intriguingly, its deletion mitigates the toxicity of human neurodegeneration factors, but the molecular mechanisms of these effects are poorly understood. Here we performed label-free quantitative global proteomics to identify crucial downstream factors, comparing two PBP1 deletion strains (DB and SM) and two cell stress conditions (heat and NaN3). In all four analyses, downregulations of key bioenergetics enzymes (CIT1, SDH1, MLS1), cell wall mannoproteins (HSP150, PST1) and the prion protein RNQ1 as well as upregulations of the leucine biosynthesis enzyme LEU1 and the transcription factor TAF6 were documented. Consistently for both unstressed PBP1-deleted strains, over 2-fold dysregulations were documented for potential PBP1 interactors such as MKT1 or RPL39 and the stress granule component NRP1. Upregulation of the ribosomal biogenesis factor NOP10 was observed as in the mouse mutant. Consistently for both PBP1 deletion strains, heat stress triggered changes of the stress granule component GIS2 and several of its interactors.
Project description:We report gene expression profiling in the fission yeast Schizosaccharomyces pombe. We performed high-throughput sequencing of RNA isolated from wild-type, erh1â??, and ccr4â?? strains. We find that many meiotic gene containing degradation sequence DSR are expressed in vegetative erh1â??, while these meiotic mRNAs do not increase in ccr4â??, indicating that Erh1 and Ccr4 target different set of genes during vegetative growth. RNA sequencing in wild-type, erh1â?? and ccr4â?? strains. Two biological replicates for erh1â?? and ccr4â??, and one sample for wild-type because we already reported wild-type data previously.
Project description:These Affymetrix data were used to determine the role of each non-essential subunit of the conserved Ccr4-Not complex in the control of gene expression in the yeast S. cerevisiae. The study was performed with cells growing exponentially in high glucose and with cells grown to glucose depletion. Specific patterns of gene de-regulation were observed upon deletion of any given subunit, revealing the specificity of each subunit’s function. Consistently, the purification of the Ccr4-Not complex through Caf40p by tandem affinity purification from wild-type cells or cells lacking individual subunits of the Ccr4-Not complex revealed that each subunit had a particular impact on complex integrity. Furthermore, the micro-arrays revealed that the role of each subunit was specific to the growth conditions. From the study of only two different growth conditions, revealing an impact of the Ccr4-Not complex on more than 85% of all studied genes, we can infer that the Ccr4-Not complex is important for expression of most of the yeast genome. Keywords: genetic modification, stress response