Hypoxia inducible factor (HIF) is the major transcriptional regulator of cellular responses to hypoxia. The two principal HIF-a isoforms, HIF-1a and HIF-2a, are progressively stabilized in response to hypoxia and form heterodimers with HIF-1b to activate a broad range of transcriptional responses. Here we report on the pan-genomic distribution of isoform-specific HIF binding in response to hypoxia of varying severity and duration, and in response to genetic ablation of each HIF-a isoform. Our findings reveal that, despite an identical consensus recognition sequence in DNA, each HIF heterodimer loads progressively at a distinct repertoire of cell-type specific sites across the genome, with little evidence of redistribution under any of the conditions examined. Marked biases towards promoter proximal binding of HIF-1 and promoter distant binding of HIF-2 were observed under all conditions and were consistent in multiple cell type. The findings imply that each HIF isoform has an inherent property that determines its binding distribution across the genome, which might be exploited to therapeutically target the specific transcriptional output of each isoform independently. Overall design: RNA_seq analysis of hypoxic gene regulation in HKC8 and HepG2 cell lines and in RCC4 cell lines stably transfected with wtVHL
Hypoxia drives glucose transporter 3 expression through hypoxia-inducible transcription factor (HIF)-mediated induction of the long noncoding RNA NICI.
Specimen part, Cell line, Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Comparative physiology and transcriptional networks underlying the heat shock response in Populus trichocarpa, Arabidopsis thaliana and Glycine max.
Specimen part, Treatment
View SamplesThe heat shock response continues to be layered with additional complexity as interactions and cross-talk among heat shock proteins, the reactive oxygen network and hormonal signaling are discovered. However, comparative analyses exploring variation in each of these processes among species remains relatively unexplored. In controlled environment experiments, photosynthetic response curves were conducted from 22 C to 42 C and indicated that temperature optimum of light saturated photosynthesis was greater for Glycine max relative to Arabidopsis thaliana or Populus trichocarpa. Transcript profiles were taken at defined states along the temperature response curves and inferred pathway analysis revealed species-specific variation in the abiotic stress and the minor carbohydrate raffinose/galactinol pathways. A weighted gene co-expression network approach was used to group individual genes into network modules linking biochemical measures of the antioxidant system to leaf-level photosynthesis among P. trichocarpa, G. max and A. thaliana. Network enabled results revealed an expansion in the G. max HSP17 protein family and divergence in the regulation of the antioxidant and heat shock module relative to P. trichocarpa and A. thaliana. These results indicate that although the heat shock response is highly conserved, there is considerable species-specific variation in its regulation.
Comparative physiology and transcriptional networks underlying the heat shock response in Populus trichocarpa, Arabidopsis thaliana and Glycine max.
Specimen part, Treatment
View SamplesThe heat shock response continues to be layered with additional complexity as interactions and cross-talk among heat shock proteins, the reactive oxygen network and hormonal signaling are discovered. However, comparative analyses exploring variation in each of these processes among species remains relatively unexplored. In controlled environment experiments, photosynthetic response curves were conducted from 22 C to 42 C and indicated that temperature optimum of light saturated photosynthesis was greater for Glycine max relative to Arabidopsis thaliana or Populus trichocarpa. Transcript profiles were taken at defined states along the temperature response curves and inferred pathway analysis revealed species-specific variation in the abiotic stress and the minor carbohydrate raffinose/galactinol pathways. A weighted gene co-expression network approach was used to group individual genes into network modules linking biochemical measures of the antioxidant system to leaf-level photosynthesis among P. trichocarpa, G. max and A. thaliana. Network enabled results revealed an expansion in the G. max HSP17 protein family and divergence in the regulation of the antioxidant and heat shock module relative to P. trichocarpa and A. thaliana. These results indicate that although the heat shock response is highly conserved, there is considerable species-specific variation in its regulation.
Comparative physiology and transcriptional networks underlying the heat shock response in Populus trichocarpa, Arabidopsis thaliana and Glycine max.
Specimen part, Treatment
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Bacterial control of host gene expression through RNA polymerase II.
Sex, Cell line
View SamplesUrinary tract infections (UTIs) constitute a highly relevant model of microbial adaptation, in which the contrasting effects of pathogens and commensals on host tissues are clearly displayed. While virulent Escherichia coli cause severe, potentially life-threatening disease by breaking the inertia of the mucosal barrier and infecting the kidneys, the most common outcome of bacteriuria is an asymptomatic carrier state resembling commensalism at other mucosal sites. It remains unclear if the lack of destructive inflammation merely reflects low virulence or if carrier strains actively inhibit disease associated responses in the host. To address this question, we examined the effects of asymptomatic bacterial carriage on host gene expression.
Bacterial control of host gene expression through RNA polymerase II.
Sex
View SamplesUrinary tract infections (UTIs) constitute a highly relevant model of microbial adaptation, in which the contrasting effects of pathogens and commensals on host tissues are clearly displayed. While virulent Escherichia coli cause severe, potentially life-threatening disease by breaking the inertia of the mucosal barrier and infecting the kidneys, the most common outcome of bacteriuria is an asymptomatic carrier state resembling commensalism at other mucosal sites. It remains unclear if the lack of destructive inflammation merely reflects low virulence or if carrier strains actively inhibit disease associated responses in the host. To address this question, we examined the effects of asymptomatic bacterial carriage on host gene expression.
Bacterial control of host gene expression through RNA polymerase II.
Cell line
View SamplesGene expression (by Affymetrix GeneChip Human 1.0ST) profiling of biopsy samples from recurrent, platinum resistant epithelial ovarian cancer patients before and after treatment of decitabine in combination with carboplatin. The Illumina Infinium 27k Human DNA methylation Beadchip v1.2 was used to obtain DNA methylation profiles across approximately 27,000 CpGs in PBMC (14 paired samples), tumor (8 paired samples) and ascites (6 paired samples) (GSE31826).
Decitabine reactivated pathways in platinum resistant ovarian cancer.
Age
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Shp2 signaling suppresses senescence in PyMT-induced mammary gland cancer in mice.
Specimen part, Treatment
View SamplesIn this study, we have used techniques from cell biology, biochemistry, and genetics to investigate the role of the tyrosine phosphatase Shp2 in tumor cells of MMTV-PyMT mouse mammary glands. Genetic ablation or pharmacological inhibition of Shp2 induces senescence, as determined by the activation of senescence-associated -gal (SA--gal), cyclin-dependent kinase inhibitor 1B (p27), p53, and histone 3 trimethylated lysine 9 (H3K9me3). Senescence induction leads to inhibition of self-renewal of tumor cells and blockage of tumor formation and growth. A signaling cascade was identified that acts downstream of Shp2 to counter senescence: Src, Focal adhesion kinase and Map kinase inhibit senescence by activating the expression of S-phase kinase-associated protein 2 (Skp2), Aurora kinase A (Aurka), and the Notch ligand Delta-like 1 (Dll1), which block p27 and p53. Remarkably, the expression of Shp2 and of selected target genes predicts human breast cancer outcome. We conclude that therapies which rely on senescence induction by inhibiting Shp2 or controlling its target gene products may be useful in blocking breast cancer.
Shp2 signaling suppresses senescence in PyMT-induced mammary gland cancer in mice.
Specimen part, Treatment
View Samples