To understand the gene network that controls plant tolerance to cold stress, we carried out a near full genome transcript expression profiling in Arabidopsis using Affymetrix GeneChips that contain approximately 24,000 genes. For microarray analysis, Arabidopsis seedlings were cold treated at 0 C for 0 h, 3 h, 6 h, and 24 h. A total of 939 genes were statistically determined to be cold-regulated with 655 being up-regulated and 284 down-regulated. A large number of the early cold-responsive genes encode transcription factors that likely control late-responsive genes, which implies a multitude of transcriptional cascades. In addition, many genes involved in post-transcriptional and chromatin level regulation were also cold regulated suggesting their involvement in cold responsive gene regulation. A number of genes important for the biosynthesis or signaling of plant hormones, such as abscisic acid, gibberellic acid and auxin, are regulated by cold stress, which is of potential importance in coordinating cold tolerance with growth and development. We compared the cold-responsive transcriptomes of wild type and ice1, a mutant defective in an upstream transcription factor required for chilling and freezing tolerance. The transcript levels of many cold-responsive genes were altered in the ice1 mutant not only during cold stress conditions, but also before cold treatments. Our study provides a global picture of the Arabidopsis cold-responsive transcriptome and its control by ICE1, and thus will be valuable for understanding gene regulation under cold stress and the molecular mechanisms of cold tolerance.
The Arabidopsis cold-responsive transcriptome and its regulation by ICE1.
No sample metadata fields
View SamplesWe aimed to predict obesity risk with genetic data, specifically, obesity-associated gene expression profiles. Genetic risk score was computed. The genetic risk score was significantly correlated with BMI when an optimization algorithm was used. Linear regression and built support vector machine models predicted obesity risk using gene expression profiles and the genetic risk score with a new mathematical method.
A computational framework for predicting obesity risk based on optimizing and integrating genetic risk score and gene expression profiles.
Specimen part
View SamplesAE-expressing murine BM cells treated with all-trans retinoic acid (ATRA) in semi-solid methycellulose-based cultures show an increase in self-renewal capacity whilst treatment with a specific RARa agonist NRX195183 reduces their clonogenicity. Gene expression analysis was performed to further investigate the molecular mechanisms underlying these observations. Upregulated gene sets were identified in the ATRA-treated AE BM cells.
ATRA and the specific RARα agonist, NRX195183, have opposing effects on the clonogenicity of pre-leukemic murine AML1-ETO bone marrow cells.
Specimen part, Treatment
View SamplesInadequate extracellular conditions can adversely affect the environment of the ER and impinge on the maturation of nascent proteins. The resultant accumulation of unfolded proteins activates a signal transduction pathway, known as the unfolded protein response, which serves primarily to protect the cell during stress and helps restore homeostasis to the ER. Microarray analysis of the unfolded protein response in a human medulloblastoma cell line treated with thapsigargin revealed that, in addition to known targets, a large number of proangiogenic factors were up-regulated. Real-time PCR analyses confirmed that four of these factors, VEGF, FGF2, angiogenin and IL-8, were transcriptionally up-regulated in multiple cell lines by various ER stress inducers. Our studies on VEGF regulation revealed that XBP-1(S), a UPR-inducible transcription factor, bound to two regions on the VEGF promoter, and analysis of XBP-1 null mouse embryonic fibroblasts revealed that it contributes to VEGF expression in response to ER stress. ATF4, another UPR-inducible transcription factor, also binds to the VEGF gene, although its contribution to VEGF transcription appeared to be fairly modest. We also found that VEGF mRNA stability is increased in response to UPR activation, via activation of the AMP and p38MAP kinases, demonstrating that increased mRNA levels occur at two regulatory points. In keeping with the mRNA levels, we found that VEGF protein is secreted at levels as high as or higher than that achieved in response to hypoxia. Our results indicate that the UPR plays a significant role in inducing positive regulators of angiogenesis. It also regulates VEGF expression at multiple levels and is likely to have widespread implications for promoting angiogenesis in response to normal physiological cues as well as in pathological conditions like cancer.
Transcriptional and post-transcriptional regulation of proangiogenic factors by the unfolded protein response.
Treatment, Time
View SamplesRelative polysomal loading changes for wild type (N2) versus ife-1(bn127) C. elegans strains
Spatial and temporal translational control of germ cell mRNAs mediated by the eIF4E isoform IFE-1.
No sample metadata fields
View SamplesMost commonly used models of non-alcoholic steatohepatitis (NASH) are diets based on specific gene knockouts or represent extreme manipulations of diet. We have examined the effects of modest increased caloric intake and high dietary unsaturated fat content on the development of NASH in male rats using a model in which overfeeding is accomplished via intragastric infusion of liquid diets as a part of total enteral nutrition. Male Sprague dawley rats were fed diets 5% corn oil containing diets at 187 Kcal/kg3/4/d or fed 70% corn oil containing diets at 220 Kcal/kg3/4/d for a period of 3 weeks. Hepatic gene expression were assessed at the end of the study. Our results indicate that overfeeding of high unsaturated fat diets leads to pathological, endocrine and metabolic changes characteristic of NASH patients and is associated with increased oxidative stress and TNF-a.
A new model for nonalcoholic steatohepatitis in the rat utilizing total enteral nutrition to overfeed a high-polyunsaturated fat diet.
No sample metadata fields
View SamplesKaposi sarcoma is the most common cancer in AIDS patients and is typified by red skin lesions. The disease is caused by the KSHV virus (HHV8) and is recognizable by its distinctive red skin lesions. The lesions are KSHV infected spindle cells, most commonly the lymphatic endothelial and blood vessel endothelial cells (LEC and BEC), plus surrounding stroma. Here we examine KSHVs modulation of Notch signaling using wild-type LEC cells co-cultured with DLL4 and JAG1 expressing LEC cells.
KSHV manipulates Notch signaling by DLL4 and JAG1 to alter cell cycle genes in lymphatic endothelia.
No sample metadata fields
View SamplesTobacco exposure has been established to be a major risk factor for developing oral squamous cell carcinoma (OSCC). The purpose of this study is to identify potential biomarkers to distinguish the biological effectsof combustible tobacco products from that of non-combustible tobacco products using normal human gingival epithelial cells (HGEC), non-metastatic (101A) and metastatic (101B) OSCC cell lines.
AKR1C1 as a Biomarker for Differentiating the Biological Effects of Combustible from Non-Combustible Tobacco Products.
Cell line
View SamplesSystemic juvenile idiopathic arthritis (SJIA) is a chronic childhood arthropathy with features of autoinflammation. Early inflammatory SJIA is associated with expansion and activation of neutrophils with a sepsis-like phenotype, but neutrophil phenotypes present in longstanding and clinically inactive disease (CID) are unknown. The objective of this study was to examine activated neutrophil subsets, S100 alarmin release, and gene expression signatures in children with a spectrum of SJIA disease activity. Methods: Highly-purified neutrophils were isolated using a two-step procedure of density-gradient centrifugation followed by magnetic-bead based negative selection prior to flow cytometry or cell culture to quantify S100 protein release. Whole transcriptome gene expression profiles were compared in neutrophils from children with both active SJIA and CID. Results: Patients with SJIA and active systemic features demonstrated a higher number of CD16+CD62Llo neutrophil population compared to controls. This neutrophil subset was not seen in patients with CID or patients with active arthritis not exhibiting systemic features. Using imaging flow cytometry, CD16+CD62Llo neutrophils from patients with active SJIA and features of macrophage activation syndrome (MAS) had increased nuclear hypersegmentation compared to CD16+CD62L+ neutrophils. Serum levels of S100A8/A9 and S100A12 were strongly correlated with peripheral blood neutrophil counts. Neutrophils from active SJIA patients did not show enhanced resting S100 protein release; however, regardless of disease activity, neutrophils from SJIA patients did show enhanced S100A8/A9 release upon PMA stimulation compared to control neutrophils. Furthermore, whole transcriptome analysis of highly purified neutrophils from children with active SJIA identified 214 differentially expressed genes compared to neutrophils from healthy controls. The most significantly upregulated gene pathway was Immune System Process, including AIM2, IL18RAP, and NLRC4. Interestingly, this gene set showed intermediate levels of expression in neutrophils from patients with long-standing CID yet persistent serum IL-18 elevation. Indeed, all patient samples regardless of disease activity demonstrated elevated inflammatory gene expression, including inflammasome components and S100A8. Conclusion: We identify features of neutrophil activation in SJIA patients with active disease and CID, including a proinflammatory gene expression signature, reflecting persistent innate immune activation. Taken together, these studies expand understanding of neutrophil function in chronic autoinflammatory disorders such as SJIA. Overall design: Highly purified neutrophils isolated from patients with SJIA and healthy controls
Neutrophils From Children With Systemic Juvenile Idiopathic Arthritis Exhibit Persistent Proinflammatory Activation Despite Long-Standing Clinically Inactive Disease.
Specimen part, Disease, Disease stage, Subject
View SamplesSoy foods have been suggested to have both positive health benefits and potentially adverse effects largely as a result of their content of isoflavone phytoestrogens. Since soy protein isolate (SPI) contains isoflavones, in addition to purported health benefits, safety concerns have been raised regarding the use of SPI and soy formulas, because of potential estrogenic actions during the neonatal period, including the potential for reproductive toxicity, infertility, and the possibility of increased risk for development and recurrence of estrogen sensitive cancers such as breast cancer. In the current study, we used a rat model to compare the effects of SPI with those of 17b-estradiol (E2), on global gene expression profiles and morphology in the female rat mammary gland. Rats were either fed AIN-93G diets containing casein (CAS) or SPI beginning on postnatal day (PND) 30.
Mammary gland morphology and gene expression differ in female rats treated with 17β-estradiol or fed soy protein isolate.
Sex
View Samples