Upon induction of DNA damage Arabidopsis thaliana plants initiate a transcriptional response program governed by signalling cascades which are activated by the ATM and ATR kinases
GMI1, a structural-maintenance-of-chromosomes-hinge domain-containing protein, is involved in somatic homologous recombination in Arabidopsis.
Specimen part
View SamplesIRAK-4 is an essential component of the signal transduction complex downstream of the IL-1- and Toll-like receptors. Though regarded as the first kinase in the signaling cascade, the role of IRAK-4 kinase activity versus its scaffold function is still controversial. In order to investigate the role of IRAK-4 kinase function in vivo, knock-in mice were generated by replacing the wild type IRAK-4 gene with a mutant gene encoding kinase deficient IRAK-4 protein (IRAK-4 KD). Analysis of bone marrow macrophages obtained from WT and IRAK-4 KD mice with a number of experimental techniques demonstrated that the IRAK-4 KD cells greatly lack responsiveness to stimulation with the Toll-like receptor 4 (TLR4) agonist LPS. One of the techniques used, microarray analysis, identified IRAK-4 kinase-dependent LPS response genes and revealed that the induction of LPS-responsive mRNAs was largely ablated in IRAK-4 KD cells. In summary, our results suggest that IRAK-4 kinase activity plays a critical role in TLR4-mediated induction of inflammatory responses.
IRAK-4 kinase activity-dependent and -independent regulation of lipopolysaccharide-inducible genes.
No sample metadata fields
View SamplesThe retinas of simian primates include a specialized, cone-rich, macula which regards the central visual field and mediates high acuity and colour vision. A prominent feature of the macula is the fovea centralis - a 1 mm-wide, avascular depression in the inner retinal surface that corresponds with a local absence of rods and a peak spatial density of cones in the outer photoreceptor layer. The arrangement of macular photoreceptors, and their specialized midget circuits, are the neural substrate for high resolution vision in primates. Macular-specific photoreceptor loss and abnormal blood vessel growth within the macula are the major causes of untreatable vision loss worldwide. However, the genes that regulate specialization of the macula, and the causes of its vulnerability to degeneration, remain obscure. Microarrays were used to compare gene expression between macula and non-macular regions during a critical phase of human retinal vascular development.
Differential expression of anti-angiogenic factors and guidance genes in the developing macula.
Specimen part
View SamplesThe highly conserved protein eIF5A found in archaea and all eucaryotes uniquely contains the posttranslationally formed amino acid hypusine. Despite being essential the functions of this protein and its modification remain unclear. To gain more insight into these functions temperature sensitive mutants of the human EIF5A1 were characterized in the yeast Saccharomyces cerevisiae.
Temperature-sensitive eIF5A mutant accumulates transcripts targeted to the nonsense-mediated decay pathway.
No sample metadata fields
View SamplesInflammation has a causal role in many cancers. In prostate cancers, epidemiological data suggest a link between prostatitis and subsequent cancer development, but a proof for this concept in a tumor model has been lacking. A constitutively active version of the IkappaB kinase 2 (IKK2), the molecule activated by a plethora of inflammatory stimuli, was expressed specifically in the prostate epithelium. Signaling of the IKK2/NF-kappaB axis was insufficient for transformation of prostate tissue. However, while PTEN+/- epithelia exhibited intraepithelial neoplasias only recognizable by nuclear alterations, additional IKK2 activation led to an increase in tumor size and formation of cribriform structures and to a fiber increase in the fibroblastic stroma. This phenotype was coupled with inflammation in the prostate gland characterized by infiltration of granulocytes and macrophages. Molecular characterization of the tissues showed a specific loss of smooth muscle markers as well as expression of chemokines attracting immune cells. Isolation of epithelial and stromal cells showed differential chemokine expression by these cells. Correlation studies showed the inflammatory phenotype coupled to loss of smooth muscle in infiltrated glands, but maintenance of the phenotype in glands where inflammation had decreased. Despite the loss of the smooth muscle barrier, tumors were not invasive in a stable genetic background. Data mining revealed that smooth muscle markers are downregulated in human prostate cancers and literature data show that loss of these markers in primary tumors is associated with subsequent metastasis. Our data show that loss of smooth muscle and invasiveness of the tumor are not coupled. Thus, inflammation during early steps of tumorigenesis can lead to increased tumor size and a potential change in the subsequent metastatic potential, but the tumor requires an additional transformation to become a carcinoma.
Persistent inflammation leads to proliferative neoplasia and loss of smooth muscle cells in a prostate tumor model.
Age, Specimen part
View SamplesSwiss-Webster female mice (Charles River Laboratories, Wilmington, MA) 5-6 weeks of age were infected intranasally with 5 LD50 of either WT or lpp mutant of Y. pestis CO92. Uninfected mice were used as controls. At either 12 or 48 h post infection (p.i.), 3 mice per group were euthanized and the lungs, livers, and spleens were harvested and homogenized in 1 ml of RNALater (Ambion/Applied Biosystems, Austin, TX) using 50-ml tissue homogenizers (Kendell, Mansfield, MA). RNA was isolated from the tissue homogenates and purified using RNAqueous (Ambion). After an overnight precipitation, the RNA was resuspended in 20 ul of diethylpyrocarbonate (DEPC)-treated water and hybridized to Affymetrix GeneChip Mouse Genome 430 2.0 arrays, performed by the Molecular Genomics Core at UTMB Galveston, Texas, per manufacture protocols. The arrays had 45,000 probe sets representing more than 39,000 transcripts derived from ~34,000 well-substantiated mouse genes. The experiments were performed in triplicate (biological replicates), generating a total of 45 arrays.
Comparative Analyses of Transcriptional Profiles in Mouse Organs Using a Pneumonic Plague Model after Infection with Wild-Type Yersinia pestis CO92 and Its Braun Lipoprotein Mutant.
Sex, Specimen part, Time
View SamplesAsthma is a chronic inflammatory respiratory disease affecting over 300 million people around the world. Some asthma patients remain poorly controlled by conventional therapies and experience more life-threatening exacerbations. While patients with severe, refractory disease represent a heterogeneous group, a feature shared by most includes glucocorticoid insensitivity. We sought to characterize differences in the airway smooth muscle transcriptome response to glucocorticoids in fatal asthma vs. non-asthma donors. RNA-Seq was used to measure airway smooth muscle transcript expression differences between 9 donors with fatal asthma and 8 non-asthma donors. Cells from each donor were treated with budesonide or with vehicle control. Poly(A)-selected RNA-Seq libraries were prepared with the Illumina TruSeq method. An Illumina HiSeq 2500 instrument was used to generate 125 base pair paired-end reads. Overall design: Transcriptome profiles obtained via RNA-Seq for airway smooth muscle cells from 9 fatal asthma and 8 non-asthma donors treated with budesonide (100nM for 24h) or vehicle control were compared
Airway Smooth Muscle-Specific Transcriptomic Signatures of Glucocorticoid Exposure.
Specimen part, Disease, Disease stage, Treatment, Subject
View SamplesPlants grown under a canopy recognize changes in light quality and modify their growth patterns; this modification is known as shade avoidance syndrome. In leaves, leaf blade expansion is suppressed, whereas petiole elongation is promoted under the shade. However, the mechanisms that control these responses are largely unclear. Here, we demonstrated that both auxin and brassinosteroid (BR) are required for the normal leaf responses to shade. The microarray analysis of leaf blades and petioles treated with end-of-day far-red light (EODFR) revealed that almost half of the genes induced by the treatment in both parts were previously identified as auxin-responsive genes. Likewise, BR-responsive genes were overrepresented in the EODFR-induced genes. Hence, the auxin and BR responses were elevated by EODFR treatment in both leaf blades and petioles, although opposing growth responses were observed in these two parts. The analysis of the auxin-deficient doc1/big mutant and BR-deficient rot3/cyp90c1 mutant further indicates that auxin and BR were equally required for the normal petiole elongation response to the shade stimulus. In addition, the spotlight irradiation experiment revealed that phytochrome in leaf blades but not that in petioles regulated petiole elongation, which was probably mediated through regulation of the auxin/BR responses in petioles. On the basis of these findings, we conclude that auxin and BR cooperatively promote petiole elongation in response to the shade stimulus under the control of phytochrome in the leaf blade.
Involvement of auxin and brassinosteroid in the regulation of petiole elongation under the shade.
Specimen part
View SamplesDam identification (DamID) is a powerful technique to generate genome-wide maps of chromatin protein binding. Due to its high sensitivity it is particularly suited to study the genome interactions of chromatin proteins in small tissue samples in model organisms such as Drosophila. Here we report an intein-based approach to tune the expression level of Dam and Dam-fusion proteins in Drosophila by addition of a ligand to fly food. This helps to suppress toxic effects of Dam. In addition we describe a strategy for genetically controlled expression of Dam in a specific cell type in complex tissues. We demonstrate the utility of the latter by generating a glia-specific map of Polycomb in small samples of brain tissue. Overall design: RNA sequencing of 3 samples, each using 2 biological replicates.
Inducible DamID systems for genomic mapping of chromatin proteins in Drosophila.
Sex, Specimen part, Subject
View SamplesUnlike other members of the MAPK family, ERK5 contains a large C-terminal domain with transcriptional activation capability in addition to an N-terminal canonical kinase domain. Genetic deletion of ERK5 is embryonic lethal and tissue-restricted deletions have profound effects on erythroid development, cardiac function and neurogenesis. In addition, depletion of ERK5 is anti-inflammatory and anti-tumorigenic. Small molecule inhibition of ERK5 has been shown to have promising activity in cell and animal models of inflammation and oncology. Here we report the synthesis and biological characterization of potent, selective ERK5 inhibitors. In contrast to both genetic depletion/deletion of ERK5 and inhibition with previously reported compounds, inhibition of the kinase with the most selective of the new inhibitors had no anti-inflammatory or anti-proliferative activity. The source of efficacy in previously reported ERK5 inhibitors is shown to be off-target activity on bromodomains (BRDs), conserved protein modules involved in recognition of acetyl-lysine residues during transcriptional processes. It is likely that phenotypes reported from genetic deletion or depletion of ERK5 arise from removal of a non-catalytic function of ERK5. The newly reported inhibitors should be useful in determining which of the many reported phenotypes are due to kinase activity, and delineate which can be pharmacologically targeted. Overall design: Two cellular models with reported ERK5-regulated signaling were used: Pam3CSK4-stimulated HUVECs as a model of inflammation, and EGF-stimulated HeLa cells as an established cell model of ERK5 regulation. Cells were pre-incubated with DMSO vehicle, AX15836 (ERK5 inhibitor), AX15839 (dual ERK5/BRD inhibitor), or I-BET762 (BRD inhibitor), then stimulated with agonist. Cellular responses were verified by immunoassays and western blots using replicate wells in the same experiment.
ERK5 kinase activity is dispensable for cellular immune response and proliferation.
Specimen part, Subject, Compound
View Samples