In 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 SamplesThe 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 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 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 SamplesTo study the molecular mediators of naturally rewarding effects of palatable food we used a model of palatable snacking (Ulrich-Lai et al., 2007) in which rats are given chronic, brief access to a limited amount of sucrose solution (30%). Single housed, male Long-Evans rats (250g) (n=12 per group) from Harlan Labs (Indianapolis, IN) received normal rat chow (Harlan Teklad) and water ad libitum for the duration of the experiment. After a one-week period of acclimation, rats were randomly assigned to drink treatment groups of either 30% sucrose solution or water. Rats received a 14-day regimen of twice daily (9:30 and 15:30) brief (maximum of 30 minutes) limited (up to 4 mL) access of their assigned drink solution. Drink solutions were delivered via a graduated sipper placed onto the cage top in addition to the existing water bottle and sippers were immediately removed when the animal had consumed 4mL or after the 30-minute access period, whichever occurred first. Drink intake, food intake, and body weight were monitored throughout the experiment to verify that the rats learned to drink sucrose, that they adjusted chow intake for calories consumed from sucrose (~10%), and that there was no effect on body weight gain as is normally seen with this model (Ulrich-Lai et al., 2007). Drink treatment terminated on day 14 and at 8:00 on the morning of day 15, the rats were sacrificed by rapid decapitation. BLA tissue was dissected, RNA extracted, and gene expression changes between water and sucrose groups were accessed by microarray.
Pleasurable behaviors reduce stress via brain reward pathways.
Sex, Specimen part, Treatment
View Samplesaffy_ccr_maize - affy_ccr_maize - Cinnamoyl-CoA reductase (CCR) catalyzes a key step in monolignol biosynthesis. We show that downregulation of CCR in maize was associated with lower lignin content and a strong decrease in H units. Concomitantly, these cell wall modifications were associated with higher digestibility. On another hand, immunocytochemistry indicated a modification of lignification pattern and cellulose content. Transcript profiling was used as comprehensive phenotyping tools to investigate how CCR downregulation impacted metabolism and the biosynthesis of other cell wall polymers. -2 wild type and 2 CCR mutants were compared. Plants were grown in greenhouse condition and harvested at 7-8 leaf stages.
Characterization of a cinnamoyl-CoA reductase 1 (CCR1) mutant in maize: effects on lignification, fibre development, and global gene expression.
No sample metadata fields
View SamplesSelenate is chemically similar to sulfate and can be taken up and assimilated by plants via the same transporters and enzymes. In contrast to many other organisms, selenium (Se) has not been shown to be essential for higher plants. In excess, Se is toxic and restricts development. Both Se deficiency and toxicity pose problems worldwide. To obtain better insight into the effects of Se on plant metabolism and into plant mechanisms involved in Se tolerance, the transcriptome of Arabidopsis plants grown with or without selenate was studied, and Se-responsive genes identified. Roots and shoots exhibited different Se-related changes in gene regulation and metabolism. Many genes involved in sulfur (S) uptake and assimilation were upregulated. Accordingly, Se treatment enhanced sulfate levels in plants, but the quantity of organic S metabolites decreased. Transcripts regulating the synthesis and signaling of ethylene and jasmonic acid were also upregulated by Se. Selenate appeared to repress plant development, as suggested by the down-regulation of genes involved in cell wall synthesis and auxin-regulated proteins. The Se-responsive genes discovered in this study may help create plants that can better tolerate and accumulate Se, which may enhance the effectiveness of Se phytoremediation or serve as Se-fortified food.
Transcriptome analyses give insights into selenium-stress responses and selenium tolerance mechanisms in Arabidopsis.
No sample metadata fields
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 SamplesThis SuperSeries is composed of the SubSeries listed below.
Role of Tet1/3 Genes and Chromatin Remodeling Genes in Cerebellar Circuit Formation.
Specimen part
View SamplesTranscriptome analysis of mRNA samples purified from developing cerebellar granule cells and ES cell-derived granule cells using translating ribosome affinity purification (TRAP) method.
Role of Tet1/3 Genes and Chromatin Remodeling Genes in Cerebellar Circuit Formation.
Specimen part
View Samples