The extent to which carbon flux is directed towards fermentation vs. respiration differs between cell types and environmental conditions. Understanding the basic cellular processes governing carbon flux is challenged by the complexity of the metabolic and regulatory networks. To reveal the genetic basis for natural diversity in channeling carbon flux, we applied Quantitative Trait Loci analysis by phenotyping and genotyping hundreds of individual F2 segregants of budding yeast that differ in their capacity to ferment the pentose sugar xylulose. Causal alleles were mapped to the RXT3 and PHO23 genes, two components of the large Rpd3 histone deacetylation complex. We show that these allelic variants modulate the expression of SNF1/AMPK-dependent respiratory genes. Our results suggest that over close evolutionary distances, diversification of carbon flow is driven by changes in global regulators, rather than adaptation of specific metabolic nodes. Such regulators may improve the ability to direct metabolic fluxes for biotechnological applications. Overall design: mRNA profiles of S. cerevisiae strain BY4741 with either the RXT3 or PHO23 genes either deleted, replaced by S. cerevisiae T73 allele or replaced by S. cerevisiae PHO23 allele
Natural Diversity in Pentose Fermentation Is Explained by Variations in Histone Deacetylases.
Cell line, Subject
View SamplesEndometriosis, an estrogen-dependent, progesterone-resistant, inflammatory disorder affects 10% of reproductive-age women. It is diagnosed and staged at surgery, resulting in an 11-year latency from symptom onset to diagnosis, underscoring the need for less invasive, less expensive approaches. Since the uterine lining (endometrium) in women with endometriosis has altered molecular profiles, we tested whether molecular classification of this tissue can distinguish and stage disease. We developed classifiers using genomic data from n=148 archived endometrial samples from women with endometriosis or without endometriosis (normal controls or with other common uterine/pelvic pathologies) across the menstrual cycle and evaluated their performance on independent sample sets. Classifiers were trained separately on samples in specific hormonal milieu, using margin tree classification, and accuracies were scored on independent validation samples. Classification of samples from women with endometriosis or no endometriosis involved two binary decisions each based on expression of specific genes. These first distinguished presence or absence of uterine/pelvic pathology and then no endometriosis from endometriosis, with the latter further classified according to severity (minimal/mild or moderate/severe). Best performing classifiers identified endometriosis with 90-100% accuracy, were cycle phase-specific or independent, and utilized relatively few genes to determine disease and severity. Differential gene expression and pathway analyses revealed immune activation, altered steroid and thyroid hormone signaling/metabolism and growth factor signaling in endometrium of women with endometriosis. Similar findings were observed with other disorders versus controls. Thus, classifier analysis of genomic data from endometrium can detect and stage pelvic endometriosis with high accuracy, dependent or independent of hormonal milieu. We propose that limited classifier candidate-genes are of high value in developing diagnostics and identifying therapeutic targets. Discovery of endometrial molecular differences in the presence of endometriosis and other uterine/pelvic pathologies raises the broader biological question of their impact on the steroid hormone response and normal functions of this tissue.
Molecular classification of endometriosis and disease stage using high-dimensional genomic data.
Specimen part
View SamplesCells constantly adapt to changes in their environment. In the majority of cases, the environment shifts between conditions that were previously encountered during the course of evolution, thus enabling evolutionary-programmed responses. In rare cases, however, cells may encounter a new environment to which a novel response is required. To characterize the first steps in adaptation to a novel condition, we studied budding yeast growth on xylulose, a sugar that is very rarely found in the wild. We previously reported that growth on xylulose induces the expression of amino-acid biosynthesis genes, in multiple natural yeast isolates. This induction occurs despite the presence of amino acids in the growth medium and is a unique response to xylulose, not triggered by any of the naturally available carbon sources tested. Propagating these strains for ~300 generations on xylulose significantly improved their growth rate. Notably, the most significant change in gene expression was the loss of amino acid biosynthesis gene induction. Furthermore, the reduction in amino-acid biosynthesis gene expression on xylulose was strongly correlated with the improvement in growth rate, suggesting that internal depletion of amino-acids presented the major bottleneck limiting growth in xylulose. We discuss the possible implications of our results for explaining how cells maintain the balance between supply and demand of amino acids during growth in evolutionary 'familiar' vs. 'novel' conditions. Overall design: mRNA profiles of 12 wt S. cerevisiae strains grown on either YPD or YP-xylulose, before and after 300 generations evolution on YP-xylulose
Rapid evolutionary adaptation to growth on an 'unfamiliar' carbon source.
Cell line, Subject
View SamplesA population of endometrial cells displaying key properties of mesenchymal stem cells (eMSC) has been identified in human endometrium. eMSC co-express CD146 and PDGFRB surface markers, have a perivascular location, and likely represent the reservoir of progenitors giving rise to the endometrial stromal fibroblast lineage. Endometrial stromal cells isolated from 16 oocyte donors and 3 benign gynecologic surgery subjects were FACS sorted into four populations: CD146+/PDGFRB+ (eMSC); CD146+/PDGFRB- (endothelial cells); CD146-/PDGFRB+ (stromal fibroblasts); CD146-/PDGFRB- (mixed population) then subjected to gene expression analysis on Affymetrix Human Gene 1.0 ST arrays, and differentially expressed genes compared between eMSC, stromal fibroblast, and endothelial cell populations. Ninety-two genes were validated by multiplex quantitative RT-PCR on seventy of these sorted cell populations. Immunohistochemistry was used to verify the perivascular location of eMSCs.Principal component analysis and hierarchical clustering showed eMSC clustering discretely near stromal fibroblasts and separately from endothelial cells. eMSC expressed pericyte markers and genes involved hypoxia response, inflammation, proteolysis, and angiogenesis/vasculogenesis all relevant to endometrial tissue breakdown and regeneration. Additionally, eMSC displayed distinct gene profiles for cell-cell communication and regulation of gene expression. Overall, the phenotype of the eMSC is that of a multipotent pericyte responsive to hypoxic, proteolytic, and inflammatory stimuli, able to induce angiogenesis, migrate and differentiate into lineage cells, and potentially respond to estradiol and progesterone. Identifying the pathways and gene families described herein in the context of the endometrial niche, will be valuable in understanding normal and abnormal endometrial development in utero and differentiation in adult uterus.
Perivascular human endometrial mesenchymal stem cells express pathways relevant to self-renewal, lineage specification, and functional phenotype.
Age, Specimen part
View SamplesIdentification of differentially expressed genes upon treatment with Eltrombopag in HL60 cells. HL60 cells were untreated, or treated with 3ug/ml of Eltrombopag for 36 hrs in RPMI with 10% FBS
Eltrombopag inhibits the proliferation of leukemia cells via reduction of intracellular iron and induction of differentiation.
Specimen part, Cell line
View SamplesWe used microarrays to detail the global program of gene expression in response to expression of either mutant (C96Y) or wild-type human proinsulin and identified distinct classes of up-regulated genes. Results provides insight into the molecular mechanisms underlying a form of neonatal diabetes.
Genetic complexity in a Drosophila model of diabetes-associated misfolded human proinsulin.
Sex, Specimen part
View SamplesHEK293T cells were transfected with the Rbp1-amr or slow (R729H-amr) -amanitin resistant subunit of RNA Pol II and selected with -amanitin 24 hours after transfection for additional 24 hours. Total RNA was extracted and global changes in gene expression were determined using microarray chips.
Disparity between microRNA levels and promoter strength is associated with initiation rate and Pol II pausing.
Cell line, Treatment
View SamplesIn cytotoxic T cells (CTL), Protein Kinase B /Akt is activated by the T cell antigen receptor (TCR) and the cytokine Interleukin 2 (IL2), in part by phosophorylation of Akt by Phospholipid dependent kinase 1 (PDK1).
Protein kinase B controls transcriptional programs that direct cytotoxic T cell fate but is dispensable for T cell metabolism.
Specimen part
View SamplesGene expression analysis on purified human long-term hematopoietic stem cells (LT-HSC; CD34+CD38-CD90+) and short-term HSC (ST-HSC; CD34+CD38-CD90-) derived from healthy control patients and patients with myelodysplastic syndrome (MDS)
Stem and progenitor cells in myelodysplastic syndromes show aberrant stage-specific expansion and harbor genetic and epigenetic alterations.
Specimen part, Disease, Disease stage
View SamplesMania is a serious neuropsychiatric condition associated with significant morbidity and mortality. Previous studies have suggested that environmental exposures can contribute to mania pathogenesis. We measured dietary exposures in a cohort of individuals with mania and other psychiatric disorders as well as in control individual without a psychiatric disorder. We found that a history of eating nitrated dry cured meat, but not other meat or fish products, was strongly and independently associated with current mania (adjusted odds ratio 3.49, 95% confidence interval (CI) 2.24-5.45, p<8.97x 10-8). Lower odds of association were found between eating nitrated dry cured meat and other psychiatric disorders. We further found that the feeding of meat preparations with added nitrate to rats resulted in alterations in behavior and changes in intestinal microbiota. Rats fed diets with added nitrate also showed alterations of brain pathways dysregulated in mania. These findings may lead to new methods for preventing mania and for developing novel therapeutic interventions
Nitrated meat products are associated with mania in humans and altered behavior and brain gene expression in rats.
Sex, Specimen part
View Samples