Ageing populations pose one of the main public health crises of our time. Reprogramming gene expression by altering the activities of sequence-specific transcription factors (TF) can ameliorate deleterious effects of age. Here we explore how a circuit of TFs coordinates pro-longevity transcriptional outcomes, which reveals a multi-tissue and multi-species role for an entire protein family: the E-twenty-six (ETS) TFs. In Drosophila, reduced insulin/IGF signalling (IIS) extends lifespan by coordinating activation of Aop, an ETS transcriptional repressor, and Foxo, a Forkhead transcriptional activator. Aop and Foxo bind the same genomic loci, and we show that, individually, they effect similar transcriptional programmes in vivo. In combination, Aop can both moderate or synergise with Foxo, dependent on promoter context. Moreover, Foxo and Aop oppose the activities of Pnt, an ETS transcriptional activator, effecting a transcriptomic programme that correlates lifespan outcomes. Directly limiting Pnt extended lifespan, suggesting this is how Aop and Foxo promote longevity. The lifespan-limiting role of Pnt appears to be balanced by a requirement for metabolic regulation in young flies, in which the Aop-Pnt-Foxo circuit determines nutrient storage, and Pnt regulates lipolysis and responses to nutrient stress. Molecular functions are conserved amongst ETS TFs, suggesting others may also affect ageing. We show that Ets21C limits lifespan, functioning in the same genetic network as Foxo and IIS. Other ETS TFs appear to play roles in fly ageing in multiple contexts, since inhibiting the majority of the family in intestine, adipose or neurons extended lifespan. We expand the repertoire of lifespan-limiting ETS TFs in C. elegans, confirming their conserved function in ageing. Altogether this study reveals that roles of ETS TFs in physiology and lifespan are conserved throughout the family, both within and between species. Overall design: foxo, aopACT and pntP1 overexpression in S106 D. melanogaster, polyA RNAseq.
Longevity is determined by ETS transcription factors in multiple tissues and diverse species.
Sex, Specimen part, Cell line, Subject
View SamplesGlucocorticoid excess is linked to central obesity, adipose tissue insulin resistance and type 2 diabetes mellitus. The aim of our study was to investigate the effects of dexamethasone on gene expression in human subcutaneous and omental adipose tissue, in order to identify potential novel mechanisms and biomarkers for glucocorticoid-induced insulin resistance in adipose tissue. Dexamethasone changed the expression of 527 genes in both subcutaneous and omental adipose tissue. FKBP5 and CNR1 were the most responsive genes in both depots (~7-fold increase). Dexamethasone increased FKBP5 gene and protein expression in a dose-dependent manner in both depots, but FKBP5 protein levels were 10-fold higher in omental than subcutaneous adipose tissue. FKBP5 gene expression in subcutaneous adipose tissue was positively correlated with serum insulin, HOMA-IR and subcutaneous adipocyte diameter, while fold change in gene expression by dexamethasone was negatively correlated with clinical markers of insulin resistance, i.e. HbA1c, BMI, HOMA-IR and serum insulin. Only one gene, SERTM1, clearly differed in response to dexamethasone between the two depots. Dexamethasone at high concentrations, influences gene expression in both subcutaneous and omental adipose tissue in a similar pattern and promotes gene expression of FKBP5, a gene that may be implicated in glucocorticoid-induced insulin resistance.
FKBP5 expression in human adipose tissue increases following dexamethasone exposure and is associated with insulin resistance.
Sex, Age, Specimen part
View SamplesThe goal of the study was to identify genes whose aberrant expression can contribute to diabetic retinopathy. We determined differential response in gene expression to high glucose in lymphoblastoid cell lines derived from matched type 1 diabetic individuals with and without retinopathy. Those genes exhibiting the largest difference in glucose response between diabetic subjects with and without retinopathy were assessed for association to diabetic retinopathy utilizing genotype data from a meta-genome-wide association study. All genetic variants associated with gene expression (expression QTLs; eQTLs) of the glucose response genes were tested for association with diabetic retinopathy. We detected an enrichment of the glucose response gene eQTLs among small association p-values for diabetic retinopathy. Among these, we identified FLCN as a susceptibility gene for diabetic retinopathy. Expression of FLCN in response to glucose is greater in individuals with diabetic retinopathy compared to diabetic individuals without retinopathy. Three large, independent cohorts of diabetic individuals revealed an enhanced association of FLCN eQTL to diabetic retinopathy. Mendelian randomization confirmed a direct positive effect of increased FLCN expression on retinopathy in diabetic individuals. Together, our studies integrating genetic association and gene expression implicate FLCN as a disease gene in diabetic retinopathy.
Integration of genomics and transcriptomics predicts diabetic retinopathy susceptibility genes.
Cell line
View SamplesBACKGROUND: The transcript levels of many genes exhibit significant variation in tissue samples from inbred laboratory mice. A microarray experiment was designed to separate transcript abundance variation across samples from adipose, heart, kidney, and liver tissues of C57BL/6J mice into within-mouse and between-mouse components. Within-mouse variance captures variation due to heterogeneity of gene expression within tissues, RNA-extraction, and array processing. Between-mouse variance reflects differences in transcript levels between these genetically identical mice. Many biological sources can contribute to heterogeneous transcript levels within a tissue sample including inherent stochasticity of biochemical processes such as intrinsic and extrinsic noise within cells and differences in cell-type composition which can result from heterogeneity of stem and progenitor cell populations. Differences in global signaling patterns between individuals and micro-environmental influences such as interactions with pathogens and cage mates can also contribute to variation, but are likely to contribute more to the between-mouse variance component.
Stochastic variation of transcript abundance in C57BL/6J mice.
Sex, Age, Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
CD161 defines a transcriptional and functional phenotype across distinct human T cell lineages.
Specimen part, Subject
View SamplesT lymphocytes are conventionally divided into subsets based upon expression of co-receptors, cytokines and surface molecules. By mRNA microarray analysis, T lymphocytes that express the C-type lectin CD161 were identified to share a transcriptional profile, which led to the identification of an innate function across these previously defined subsets, including CD8, CD4 and TCRgd T cells.
CD161 defines a transcriptional and functional phenotype across distinct human T cell lineages.
Specimen part
View SamplesT lymphocytes are conventionally divided into subsets based upon expression of co-receptors, cytokines and surface molecules. By mRNA microarray analysis, T lymphocytes that express the C-type lectin CD161 were identified to share a transcriptional profile, which led to the identification of an innate function across these previously defined subsets, including CD8, CD4 and TCRgd T cells.
CD161 defines a transcriptional and functional phenotype across distinct human T cell lineages.
Specimen part
View SamplesAnti-sense non-coding transcripts, genes-within-genes, and convergent gene pairs are prevalent among eukaryotes. The existence of such transcription units raises the question of what happens when RNA polymerase II (RNAPII) molecules collide head-to-head. Here we use a combination of biochemical and genetic approaches in yeast to show that polymerases transcribing opposite DNA strands cannot bypass each other. RNAPII stops, but does not dissociate upon head-to-head collision in vitro, suggesting that opposing polymerases represent insurmountable obstacles for each other. Head-to-head collision in vivo results in RNAPII stopping as well, and removal of collided RNAPII from the DNA template can be achieved via ubiquitylation-directed proteolysis. Indeed, in cells lacking efficient RNAPII poly-ubiquitylation, the half-life of collided polymerases increases, so that these can be detected between convergent genes by ChIP-Seq. These results provide new insight into fundamental mechanisms of gene traffic control, and point to an unexplored effect of anti-sense transcription on gene regulation via polymerase collision. Overall design: Total RNA was extracted from WT or Elongin C deletion mutant (elc1?) cells and strand-specific RNA-Seq was performed. Three biological replicates were performed for WT and elc1?.
RNA polymerase II collision interrupts convergent transcription.
Cell line, Subject
View SamplesNeural progenitor cells (hNPC) derived from the developing human brain can be expanded in culture and subsequently differentiated into neurons and glia. They provide an interesting source of tissue for both modeling brain development and future cellular replacement therapies. It is becoming clear that hNPC are regionally and temporally specified depending on which brain region they were isolated from and its developmental stage. We show here that hNPC derived from the developing cortex (hNPCCTX) and ventral midbrain (hNPCVM) have similar morphological characteristics and express the progenitor cell marker nestin. However, hNPCCTX cultures were highly proliferative and produced large numbers of neurons, while hNPCVM divided slowly and produced less neurons but more astrocytes. Microarray analysis revealed a similar expression pattern for some stemness markers between the two growing cultures, overlaid with a regionally specific profile that identified some important differentially expressed neurogenic transcription factors. By over expressing one of these, the transcription factor ASCL1, we were able to regain neurogenesis from hNPCVM cultures which produced larger neurons with more neurites than hNPCCTX, but no fully mature dopamine neurons. Thus hNPC are regionally specified and can be induced to undergo neurogenesis following genetic manipulation. While this restores neuronal production with a region specific phenotype, it does not restore full neurochemical maturation which may require additional factors.
Regionally specified human neural progenitor cells derived from the mesencephalon and forebrain undergo increased neurogenesis following overexpression of ASCL1.
Specimen part
View SamplesTreatment of gonadectomized mice with estradiol, dihydrotestosterone or vehicle to compare gene expression in gastrocnemius.
Stimulation of both estrogen and androgen receptors maintains skeletal muscle mass in gonadectomized male mice but mainly via different pathways.
Sex, Specimen part, Disease, Compound
View Samples