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SRP105064
Arabidopsis thaliana
24 Downloadable Samples
Illumina HiSeq 2500
Description
In plants, apical meristems allow continuous growth along the body axis. Within the root apical meristem (RAM), a group of slowly dividing quiescent center (QC) cells is thought to limit stem cell activity to directly neighboring cells (Cowels, 1956; van den Berg et al., 1997), thus endowing them with unique properties, distinct from displaced daughters. This binary identity of the stem cells stands in apparent contradiction with the more gradual changes in cell division potential (Bennett and Scheres, 2010) and differentiation (Yamaguchi et al., 2008; 2010; Furuta et al, 2014; Geldner, 2013; Masucci et al., 1996; Dolan and Costa, 2001) that occur as cells move further away from the QC. To address this paradox and to infer molecular organization of the root meristem, we used a whole-genome approach to determine dominant transcriptional patterns along root ontogeny zones. We found that the prevalent patterns are expressed in two opposing gradients. One is characterized by genes associated with development, the other enriched in differentiation genes. We confirmed these transcript gradients, and demonstrate that these translate to gradients in protein accumulation and gradual changes in cellular properties. We also show that gradients are genetically controlled through multiple pathways. Based on these findings, we propose that cells in the Arabidopsis root meristem gradually transition from 'stemness' towards differentiation. Overall design: This study contains high-resolution datasets from cell populations from the enitre root meristem and xylem-specific cell populations. Using fluorescence activated cell sorting, three cell populations were isolated based on their GFP expression intensity. Two-Three replicates were used per sample
Publication Title
Framework for gradual progression of cell ontogeny in the <i>Arabidopsis</i> root meristem.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Arabidopsis thaliana
- 9 Downloadable Samples
Arabidopsis Gene 1.0 ST Array (aragene10st)
Description
Land plants can reproduce sexually by developing an embryo from a fertilized egg cell. However, embryos can also be formed from other cell types in many plant species. A key question is thus how embryo identity in plants is controlled, and how this process is modified during non-zygotic embryogenesis. The Arabidopsis zygote divides to produce an embryonic lineage and an extra-embryonic suspensor. Yet, normally quiescent suspensor cells can develop a second embryo when the initial embryo is damaged, or when response to the signaling molecule auxin is locally blocked. Here we have used auxin-dependent suspensor embryogenesis as a model to determine transcriptome changes during embryonic reprogramming. We find that reprogramming is complex and accompanied by large transcriptomic changes prior to anatomic changes. This analysis revealed a strong enrichment for genes encoding components of auxin homeostasis and response among misregulated genes. Strikingly, deregulation among multiple auxin-related gene families converged upon re-establishment of cellular auxin levels or response. This suggests a remarkable degree of feedback regulation to create resilience in auxin response during embryo development. Starting from the transcriptome of auxin-deregulated embryos, we identify an auxin-dependent bHLH transcription factor network that mediates the activity of this hormone in suppressing embryo development from the suspensor.
Publication Title
A Robust Auxin Response Network Controls Embryo and Suspensor Development through a Basic Helix Loop Helix Transcriptional Module.
Sample Metadata Fields
Specimen part
View Samples- Arabidopsis thaliana
- 44 Downloadable Samples
- Arabidopsis Gene 1.1 ST Array (aragene11st)
Description
SuperSeries contain expression data from the nuclei of cell types involved in patterning events, with focus on root apical stem cell formation, at 16-cell stage, early globular stage and late globular stage in the early Arabidopsis embryo (atlas). Expression data comparing nuclear and cellular RNA isolated from whole 16-cell stage Arabidopsis embryos is also included.
Publication Title
Transcriptome dynamics revealed by a gene expression atlas of the early Arabidopsis embryo.
Sample Metadata Fields
Specimen part
View Samples- Arabidopsis thaliana
- 38 Downloadable Samples
- Arabidopsis Gene 1.1 ST Array (aragene11st)
Description
The establishement of the first plant tissues occurs during embryo development. Indeed, cell types that will form the Arabidopsis root stem cell niche are first specified during 16-cell (16C), early globular (EG) and late globular (LG) stage of embryonic development. While some regulatory factors are known, we do not yet understand the genetic networks underlying the specification of these cell types. One main reason for this is the difficulties in adapting genome-wide approaches to the cellular level. Here, we have adapted such an approach (INTACT) to generate microarray-based cell type-specific transcriptomic profiles at 16C to LG stage for use in determining the role of the transcriptome in cell specification and differentiation during root stem cell niche formation.
Publication Title
Transcriptome dynamics revealed by a gene expression atlas of the early Arabidopsis embryo.
Sample Metadata Fields
Specimen part
View Samples- Rattus norvegicus
- 26 Downloadable Samples
- Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
Acute progressive feed restriction (APFR) represents a specific form of caloric restriction in which feed availability is increasingly curtailed over a period of a few days to a few weeks. It is often used for control animals in toxicological and pharmacological studies on compounds causing body weight loss to equalize weight changes between experimental and control groups and thereby, intuitively, to also set their metabolic states to the same phase. However, scientific justification for this procedure is lacking. In the present study, we analyzed by DNA microarrays the impact on hepatic gene expression in rats of two APFR regimens that caused identical diminution of body weight (19%) but differed slightly in duration (4 vs. 10 days). In addition, white adipose tissue (WAT) was also subjected to the transcriptomic analysis on day-4. The data revealed that the two regimens led to distinct patterns of differentially expressed genes in liver, albeit some major pathways of energy metabolism were similarly affected (particularly fatty acid and amino acid catabolism). The reason for the divergence appeared to be entrainment by the longer APFR protocol of peripheral oscillator genes, which resulted in derailment of circadian rhythms and consequent interaction of altered diurnal fluctuations with metabolic adjustments in gene expression activities. WAT proved to be highly unresponsive to the 4-day APFR as only 17 mRNA levels were influenced by the treatment. This study demonstrates that body weight is a poor proxy of metabolic state and that the customary protocols of feed restriction can lead to rhythm entrainment.
Publication Title
Genome-wide effects of acute progressive feed restriction in liver and white adipose tissue.
Sample Metadata Fields
No sample metadata fields
View Samples- Arabidopsis thaliana
- 17 Downloadable Samples
- Arabidopsis Gene 1.0 ST Array (aragene10st)
Description
Coordination of cell division and pattern formation is central to tissue and organ development, and is particularly important in plants where walls prevent cell migration. Auxin and cytokinin are both critical for division and patterning, but it is unknown how these hormones converge to control tissue development. Here, we identify a genetic network that reinforces an early embryonic bias in auxin distribution to create a local, non-responding cytokinin source within the root vascular tissue. We provide experimental and theoretical evidence that these cells act as a local tissue organizer by positioning the domain of oriented cell divisions. We further demonstrate that the auxin-cytokinin interaction acts as a spatial incoherent feed forward loop, which is essential to generate distinct hormonal response zones, thus establishing a stable pattern within a growing vascular tissue.
Publication Title
Plant development. Integration of growth and patterning during vascular tissue formation in Arabidopsis.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Rattus norvegicus
- 6 Downloadable Samples
- Affymetrix Rat Gene 1.0 ST Array (ragene10st)
Description
Prothrombin (PT) and osteopontin (OPN) promotes adhesion of different TRAP-positive multinucleated cells isolated from rat long bone (Hu et al. Exp Cell Res. 2008; 314: 638-50). The PT-adhering cell could represent either an immature precursor to the OPN-adherent osteoclast or constitute a distinct multinucleated cell population with a unique role in bone. Herein, phenotypic differences between PT- and OPN- cells were investigated with microarray- expression analysis. Characteristic for PT-cells was expression of innate immune response genes and scavenger receptors whereas OPN-cells expressed typical osteoclast proteins such as collagenases implicated in bone degradation.
Publication Title
Isolation and phenotypic characterization of a multinucleated tartrate-resistant acid phosphatase-positive bone marrow macrophage.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 21 Downloadable Samples
- Affymetrix Human Genome U219 Array (hgu219)
Description
Target specific short single-stranded DNA (ssDNA) molecules, called aptamers, are auspicious ligands for numerous in vivo applications. However, aptamers are synthetic molecules, which might be recognized by the immune cells in vivo and induce an activation of the innate immune system. Thus, immune activation potential of synthetic ssDNA oligonucleotides (ODNs) was determined using a well established closed-loop circulation model. Fresh human blood was incubated at 37C for 2 or 4 hours with ssDNA ODNs (SB_ODN) or CpG ODN as positive control. Transcriptional changes were determined by microarray analyses. Blood samples containing SB_ODN demonstrated after 4 hours a significant regulation of 295 transcripts. Amongst others, CCL8, CXCL10, CCL7 and CXCL11 were highest regulated genes. Gene Ontology terms and KEGG pathway analyses exhibited that the differentially expressed genes belong to the transcripts that are regulated during an immune and inflammatory response, and were overrepresented in TLR signaling pathway. This study shows for the first time the potential of aptamers to activate immune system after systemic application into the human blood. Thus, we highly recommend performing of these preclinical tests with potential aptamer-based therapeutics.
Publication Title
Potential capacity of aptamers to trigger immune activation in human blood.
Sample Metadata Fields
Sex, Specimen part, Treatment, Subject, Time
View Samples- Homo sapiens
- 6 Downloadable Samples
- Illumina HiSeq 2000
Description
Current pharmacotherapies for symptomatic benign prostatic hyperplasia (BPH), an androgen receptor (AR) driven, inflammatory disorder affecting elderly men, include 5a-reductase (5AR) inhibitors (i.e. dutasteride and finasteride) to block the conversion of testosterone to the more potent AR ligand dihydrotestosterone (DHT). Since DHT is the precursor for estrogen receptor ß (ERß) ligands, 5AR inhibitors could potentially limit ERß activation, which maintains prostate tissue homeostasis. We have uncovered signaling pathways in BPH-derived prostate epithelial cells (BPH-1) that are impacted by 5AR inhibition. The induction of apoptosis and repression of the cell-adhesion protein E-cadherin by the 5AR inhibitor, dutasteride, requires both ERß and TGFß. Dutasteride also induces cyclooxygenase type 2 (COX-2), which functions in a negative-feedback loop in TGFß and ERß signaling pathways as evidenced by the potentiation of apoptosis induced by dutasteride or finasteride upon pharmacological inhibition or shRNA-mediated ablation of COX-2. Concurrently, COX-2 positively impacts ERß action through its effect on the expression of a number of steroidogenic enzymes in the ERß-ligand metabolic pathway. Therefore, effective combination pharmacotherapies, which have included non-steroidal anti-inflammatory drugs, must take into account biochemical pathways affected by 5AR inhibition and opposing effects of COX-2 on the tissue protective action of ERß. Overall design: Next-generation sequencing (n=3) of shRNA mediated knockdown of COX-2 or scrambled control in BPH-1 prostate epithelial cell line
Publication Title
Opposing Effects of Cyclooxygenase-2 (COX-2) on Estrogen Receptor β (ERβ) Response to 5α-Reductase Inhibition in Prostate Epithelial Cells.
Sample Metadata Fields
Specimen part, Cell line, Subject
View Samples- Mus musculus
- 20 Downloadable Samples
- Affymetrix Mouse Gene 1.0 ST Array (mogene10st)
Description
Analysis of genes regulated by Maf and donwstream of ErbB2 in P8 Schwann cells
Publication Title
Maf links Neuregulin1 signaling to cholesterol synthesis in myelinating Schwann cells.
Sample Metadata Fields
Specimen part
View Samples