The goal of the experiment was to perform a large scale study of circadian regulation of gene expression in maize. To identify maize genes with expression regulated by the circadian clock, transcript levels in the aerial tissues of young maize seedlings were determined by transcriptional profiling with the Affymetrix GeneChip Maize Genome Array. Maize inbred B73 seedlings were grown inside Conviron growth chamber. B73 seedlings were grown for 7 days under 12 h light:12 h dark (LD) photocycles, 26 C temperature and 70% humidity. At the 8th day, seedlings were transferred to continuous light (LL) and were allowed to entrain completely for 24 h prior to tissue harvest following which tissue was harvested every 4 hours under LL conditions for a period of 48h. Therefore, for the circadian LL time course 12 time points were collected as follows (also defined as factors in the treatment section): ZT0 - 8:00 am/ subjective dawn/ Day1 ZT4 - 12:00 pm/ subjective mid-day/ Day1 ZT8 - 4:00 pm/ subjective late-day/ Day1 ZT12 - 8:00 pm/ subjective dusk/ Day1 ZT16 - 12:00 am/ subjective mid-night/ Day1 ZT20 - 4:00 am/ subjective pre-dawn/ Day1 ZT24- 8:00 am/ subjective dawn/ Day2 ZT28 - 12:00 pm/ subjective mid-day/ Day2 ZT32 - 4:00 pm/ subjective late-day/ Day2 ZT36 - 8:00 pm/ subjective dusk/ Day2 ZT40 - 12:00 am/ subjective mid-night/ Day2 ZT44 - 4:00 am/ subjective pre-dawn/ Day2 Tissue comprised of aerial portion of the seedlings (corresponding to tissue from the prop roots and up) for RNA isolation. Total RNA was isolated from the entire aerial portion of 7 day-old seedlings (corresponding to tissue from the prop roots and up) by Trizol extraction followed by Qiagen RNeasy columns and treatment with RNase-free DNase I (Qiagen; qiagen.com). RNA was isolated from 3 independent biological replicates was pooled. cRNA was generated from pooled total RNA from 3 biological replicates with the GeneChip One-Cycle Target Labeling kit according to the manufacturers recommendations (Affymetrix, affymetrix.com). The University of California, Berkeley Functional Genomics Laboratory hybridized samples to Affymetrix GeneChip Maize Genome Arrays and scanned the washed arrays as suggested by manufacturer. Probe sets called Not Present or Marginal on one or more microarrays were removed from the downstream analysis, as is common practice with circadian studies. Raw hybridization intensities were normalized across all twelve arrays using RMA express in Perfect Match mode. ****[PLEXdb(http://www.plexdb.org) has submitted this series at GEO on behalf of the original contributor, Frank G. Harmon. The equivalent experiment is ZM28 at PLEXdb.]
Coordination of the maize transcriptome by a conserved circadian clock.
Specimen part, Treatment, Time
View SamplesEmbryonic chicken telencephalon nuclei were isolated for RNAseq to identify transcripts differentially expressed across different brain regions.
Neocortical Association Cell Types in the Forebrain of Birds and Alligators.
Sex, Specimen part
View SamplesThe ER stress inducing agent Thapsigargin (TG) and/or the cytoprotective agent Salubrinal were applied to lymphoblastoid cell lines. TG induced lytic replication as well as a distinct pattern of gene expression changes. This study was designed to identify host genes mediating lytic replication secondary to ER stress.
Endoplasmic reticulum stress causes EBV lytic replication.
Specimen part, Treatment, Time
View SamplesSwiss-Webster B mouse postnatal day 4-5 primary cerebellar culture (pooled from litter mates) treated with sonic hedgehog (Shh), controls (veh), growth arrested (arrest), cycloheximide (cyc) for 1, 3 and 24 hours.
Identification of genes expressed with temporal-spatial restriction to developing cerebellar neuron precursors by a functional genomic approach.
Specimen part
View SamplesPurpose: The oxidation resistance gene 1 (OXR1) is crucial for protecting against oxidative stress, limiting neurodegeneration and maintaining normal lifespan in eukaryotes. However, the molecular function of OXR1 is still unknown. Previously we showed that human OXR1 regulates expression of antioxidant genes GPX2 and HO-1 via the p21 signaling pathway. To examine the role of hOXR1 in global transcription regulation during cellular stress, we employed RNA sequencing to investigate the transcription profile in hOXR1 depleted HeLa cells. Methods: Control siRNA (siCon) and human OXR1 siRNA (siOXR1) transfected HeLa cells were either harvested directly (siCon_NT, siOXR1_NT) or exposed to 0.5 mM H2O2 for 1 h and then harvested immediately without recovery (siCon_R0h, siOXR1_R0h). Total RNA pooled from duplicate samples was used for RNA sequencing on an Illumina HiSeq2000 platform. The sequence reads that passed quality filters were analyzed at gene level. The Blast2GO program was used to generate gene ontology (GO) annotation of differentially expressed genes (DEGs).The WEGO software was used to further perform GO functional classification and to predict pathways affected. qRT–PCR validation was performed using SYBR Green assays. Results: In total, in non-treated and hydrogen peroxide exposed cells, hOXR1 depletion results in the down-regulation of 554 genes and the up-regulation of 253 genes. These differentially expressed genes include transcription factors (i.e. HIF1A, SP6, E2F8 and TCF3) and numerous genes of the p53 signaling pathway involved in cell-cycle arrest (i.e. cyclin D, CDK6 and p21) and apoptosis (i.e. CytC and CASP9). Western blot analysis reveals that hOXR1 suppresses CASP9 protein expression and reduces post-translational cleavage into its active form. After exposure to hydrogen peroxide (1 h), 56 early response genes were up-regulated in hOXR1 depleted cells, in which 38 of these genes were not induced in control cells. In addition, a subset of the commonly up-regulated early response genes showed a stronger induction in hOXR1 depleted cells (i.e. FOS, JUN and DUSP1). Out of a total of 52 differentially expressed transcription factors in hOXR1 depleted cells under normal physiology and oxidative stress condition, 14 genes (including HIF1A, STAT5A, E2F8 and TCF3) are differentially regulated under H2O2 treatment in hOXR1 silenced cells as compared to control cells. Finally, we demonstrate that hOXR1 depleted cells undergo cell cycle arrest in G2/M phase during oxidative stress. Conclusions: Human OXR1 is important for regulation of the early stress response to oxidative stress in HeLa cells. HOXR1 modulates the p53 signaling pathway via regulation of genes involved in cell cycle arrest, apoptosis and anti-oxidation. Further, hOXR1 regulates numerous transcription factors of importance for cellular stress responses. In summary, hOXR1 may act as a sensor of cellular oxidative stress to regulate the transcriptional networks required to detoxify reactive oxygen species (ROS) and modulate cell cycle arrest and cell death (apoptosis). Overall design: The mRNA profiles of hOXR1 depleted and control Hela cells with or without H2O2 treatment 1 h were generated by RNA sequencing using Illumina Hiseq 2000.
Transcriptome analysis of human OXR1 depleted cells reveals its role in regulating the p53 signaling pathway.
No sample metadata fields
View SamplesEpstein-Barr virus (EBV) is an oncogenic virus that is associated with the pathogenesis of several human lymphoid malignancies, including Hodgkin's lymphoma. Infection of normal resting B cells with EBV results in activation to lymphoblasts that are phenotypically similar to those generated by physiological stimulation with CD40L plus IL-4. One important difference is that infection leads to the establishment of permanently growing lymphoblastoid cell lines, whereas CD40L/IL-4 blasts have finite proliferation life-spans. To identify early events which might later determine why EBV infected blasts go on to establish transformed cell lines, we performed global transcriptome analyses on resting B cells and on EBV and CD40L/IL-4 blasts after 7 days culture. As anticipated, there was considerable overlap in the transcriptomes of the two types of lymphoblasts when compared to the original resting B cells, reflecting common changes associated with lymphocyte activation and proliferation.
Induction of interferon-stimulated genes on the IL-4 response axis by Epstein-Barr virus infected human b cells; relevance to cellular transformation.
No sample metadata fields
View SamplesIschemic heart failure after acute myocardial infarction (AMI) is a major cause of morbidity and mortality worldwide. We recently reported that activation of a trans-valvular axial-flow pump in the LV and delaying myocardial reperfusion, known as Primary Unloading, limits infarct size by reducing LV wall stress and increasing expression of the cardioprotective cytokine, stromal derived factor 1 alpha (SDF1a). The mechanisms underlying the cardioprotective benefit and sustained effect of Primary Unloading remain poorly understood. We now tested the importance of delayed reperfusion, the functional significance of SDF1a, and the late-term impact on myocardial function and scar size associated with Primary Unloading.
Left Ventricular Unloading Before Reperfusion Promotes Functional Recovery After Acute Myocardial Infarction.
Sex, Specimen part, Treatment
View SamplesZnO and TiO2 nanoparticles can elicit a range of perturbed cell responses in vitro. Exposure to topically applied sunscreens containing ZnO or TiO2 particles may or may not elicit a biological effect in mice. We aimed to compare the biological responses of immune-competent hairless mice receiving topical applications of commercially available sunscreens with or without metal oxide nanoparticles, with the responses of mice receiving no sunscreen.
Long-term exposure to commercially available sunscreens containing nanoparticles of TiO2 and ZnO revealed no biological impact in a hairless mouse model.
Specimen part, Time
View SamplesIdentification of common mechanisms underlying organ development and primary tumor formation should yield new insights into tumor biology and facilitate the generation of relevant cancer models. We have developed a novel method to project the gene expression profiles of medulloblastomas (MBs)human cerebellar tumorsonto a mouse cerebellar development sequence: postnatal days 1-60 (P1-P60). Genomically, human medulloblastomas were closest to mouse P1-P10 cerebella, and normal human cerebella were closest to mouse P30-P60 cerebella. Furthermore, metastatic MBs were highly associated with mouse P5 cerebella, suggesting that a clinically distinct subset of tumors is identifiable by molecular similarity to a precise developmental stage. Genewise, down- and up-regulated MB genes segregate to late and early stages of development, respectively. Comparable results for human lung cancer vis-a-vis the developing mouse lung suggest the generalizability of this multiscalar developmental perspective on tumor biology. Our findings indicate both a recapitulation of tissue-specific developmental programs in diverse solid tumors and the utility of tumor characterization on the developmental time axis for identifying novel aspects of clinical and biological behavior.
Conserved mechanisms across development and tumorigenesis revealed by a mouse development perspective of human cancers.
No sample metadata fields
View SamplesBy comparing to common tumor cells, genes were differencially expressed in pseudopalisading cells in human glioblastoma
Histology-based expression profiling yields novel prognostic markers in human glioblastoma.
No sample metadata fields
View Samples