Project description:<p>Gene expression is a biological process regulated at different molecular levels, including chromatin accessibility, transcription, and RNA maturation and transport. In addition, these regulatory mechanisms have strong links with cellular metabolism. Here we present a multi-omics dataset that captures different aspects of this multi-layered process in yeast. We obtained RNA-seq, metabolomics, and H4K12Ac ChIP-seq data for wild-type and mip6delta strains during a heat-shock time course. Mip6 is an RNA-binding protein that contributes to RNA export during environmental stress and is informative of the contribution of post-transcriptional regulation to control cellular adaptations to environmental changes. The experiment was performed in quadruplicate, and the different omics measurements were obtained from the same biological samples, which facilitates the integration and analysis of data using covariance-based methods. We validate our dataset by showing that ChIP-seq, RNA-seq and metabolomics signals recapitulate existing knowledge about the response of ribosomal genes and the contribution of trehalose metabolism to heat stress.</p>
Project description:Heat shock induces rapid modification of proteins with SUMO2/3. This study concentrated in charaterizing how these changes are reflected on SUMOylation of chromatin bound proteins, trancsription, and chromatin binding of SUMO ligase PIAS1. Comparison of chromatin SUMO2/3 modification pattern in non-stressed and heat shocked K562 and VCaP cells. All samples were done as biological replicates. In K562 cells, SUMO2/3 ChIP-seq was done in non-stressed (37C) and heat shocked (30min at 43C) cells. The effect of heat shock factor 1 (HSF1) to chromatin SUMOylation in HS was studied in HSF1 silenced (shHSF1) K562 cells (non-stressed vs. heat shocked) using scramble shRNA transfected cells as control (shSCR). SUMO2/3, SUMO ligase PIAS1,and RNA polymerase II binding in HS (30 min at 43C) and recovery from HS (1h at 37C after HS) was studied using ChIP-seq. Effect of PIAS1 for chromatin SUMOylation was studied in PIAS1 silenced (siRNA for PIAS1, siPIAS1) cells (non-stressed or heat shocked) using non-targeting siRNA transfected cells as a control (siNON). Effect of SUMOylation to chromatin binding of RNA polymerase II was studied in UBE2I silenced (siRNA for UBE2I) and control (non-targeting siRNA transfected, siNON) VCaP cells (non-stressed or heat shocked). Effect of transtription inhibition for chromatin SUMOylation was studied in TRP (triptolide; 1 micromolar, 3h) and DRB (5,6-Dichlorobenzimidazole 1-beta-D-ribofuranosidase; 100 micromolar, 3h) treated VCaP cells. GRO-seq was used to determine HS-induced changes in nascent transcription in K562 cells.
Project description:Most SUMO-modified proteins in budding yeast and human cells are associated with chromatin. To determine specifically where sumoylated proteins are found across the genome, we performed ChIP-seq with a SUMO antibody in budding yeast. We identified 603 loci that each contain a stable SUMO peak. In agreement with a previous study, most of these sites correspond to tRNA genes or genes that encode ribosomal proteins (RPGs). However, 147 of the SUMO peaks in our analysis are found at promoters of protein-coding genes that are not RPGs (non-RPGs), many of which are among the most highly expressed genes. By comparing our data with other ChIP-seq studies, we determined that non-RPG SUMO peaks are situated precisely where general transcription factors (GTFs) assemble, but not where RNA polymerase II (RNAPII) or other promoter-proximal proteins bind. In support of this, we determined that the large subunit of TFIIF is the major SUMO target among GTFs and propose that its sumoylation controls the dynamics of RNAPII gene association. Additionally, we found that exposing yeast to a brief heat shock significantly reduces the intensity of SUMO peaks at most genes of all classes, which likely reflects the vast transcriptional reprogramming that occurs in response to temperature stress.
Project description:Heat shock induces rapid modification of proteins with SUMO2/3. This study concentrated in charaterizing how these changes are reflected on SUMOylation of chromatin bound proteins, trancsription, and chromatin binding of SUMO ligase PIAS1.
Project description:To understand the function and regulation of the C. elegans heat shock factor (HSF-1) in larval development, we have used ChIP-seq to analyze the occupancy of HSF1 and RNA Pol II in L2 larvae and young adult (YA) animals grown at 20°C or upon heat shock at 34°C for 30 min. In addition, we have used RNA-seq to analyze the transcriptomes of wild type (N2), hsf-1(ok600) mutants and hsf-1(ok600); rmSi1[hsf-1::gfp] L2 larvae grown at 20°C and characterized the gene expression change by heat shock in wild type (N2) animals at L2 stage.
Project description:Heat-Shock Factor 1 (HSF1), master regulator of the heat-shock response, facilitates malignant transformation, cancer cell survival and proliferation in model systems. The common assumption is that these effects are mediated through regulation of heat-shock protein (HSP) expression. However, the transcriptional network that HSF1 coordinates directly in malignancy and its relationship to the heat-shock response have never been defined. By comparing cells with high and low malignant potential alongside their non-transformed counterparts, we identify an HSF1-regulated transcriptional program specific to highly malignant cells and distinct from heat shock. Cancer-specific genes in this program support oncogenic processes: cell-cycle regulation, signaling, metabolism, adhesion and translation. HSP genes are integral to this program, however, even these genes are uniquely regulated in malignancy. This HSF1 cancer program is active in breast, colon and lung tumors isolated directly from human patients and is strongly associated with metastasis and death. Thus, HSF1 rewires the transcriptome in tumorigenesis, with prognostic and therapeutic implications. ChIP-seq was used to characterize HSF1 binding