To understand the effect of high and low GA levels on plant metabolism and development in Arabidopsis we made use of the GA biosynthesis inhibitor paclobutrazol (PBZ) and exogenously applied GA. The whole genome response at the translation level was assessed by immunopurification of polysomes from PBZ- and GA treated plants expressing FLAG-tagged ribosomal protein L18 (RPL18B). Polysomal associated RNA was isolated and subjected to affymterix ATH1 CHIP analysis. A total of 140 genes were statistically determined to be differentially translated after GA treatment whereas 89 genes where affected PBZ treatment. Our analysis revealed that GA and PBZ have opposing effects on the expression of cell wall and wax layer biosynthesis related genes. In addition, many genes involved in secondary metabolism are upregulated upon PBZ treatment. A set of SAUR-like genes important for mediating auxin responses are downregulated by PBZ, which is of interest to coordinatian of GA levels with growth and development. Interestingly, GA treatment induces the upregulation of transcription factors related to plant defense and senescence, which is in agreement with the early flowering upon GA treatment. Our study provides a first picture of the response of Arabidopsis to altered GA levels at the translation level, and thus will be valuable for understanding gene regulation at the polysome level.
Translatome and metabolome effects triggered by gibberellins during rosette growth in Arabidopsis.
Specimen part, Treatment
View SamplesACTH-dependent hypercortisolism caused by a pituitary adenoma [Cushings disease (CD)] is the most common cause of endogenous Cushings syndrome. CD is often associated with several morbidities, including hypertension, diabetes, osteoporosis/bone fractures, secondary infections, and increased cardiovascular mortality. While the majority (80%) of the corticotrophinomas visible on pituitary magnetic resonance imaging are microadenomas (MICs, <10 mm of diameter), some tumors are macroadenomas (MACs, 10 mm) with increased growth potential and invasiveness, exceptionally exhibiting malignant demeanor. In addition, larger and invasive MACs are associated with a significant increased risk of local complications, such as hypopituitarism and visual defects. Given the clinical and molecular heterogeneity of corticotrophinomas, the aim of this study was to investigate the pattern of genetic differential expression between MIC and MAC, including the invasiveness grade as a criterion for categorizing these tumors. In this study, were included tumor samples from patients with clinical, laboratorial, radiological, and histopathological diagnosis of hypercortisolism due to an ACTH-producing pituitary adenoma. Differential gene expression was studied using an Affymetrix microarray platform in 12 corticotrophinomas, classified as non-invasive MIC (n = 4) and MAC (n = 5), and invasive MAC (n = 3), according to modified Hardy criteria. Somatic mutations in USP8 were also investigated, but none of the patients exhibited USP8 variants. Differential expression analysis demonstrated that non-invasive MIC and MAC have a similar genetic signature, while invasive MACs exhibited a differential expression profile. Among the genes differentially expressed, we highlighted CCND2, ZNF676, DAPK1, and TIMP2, and their differential expression was validated through quantitative real-time PCR in another cohort of 15 non-invasive and 3 invasive cortocotrophinomas. We also identified potential biological pathways associated with growth and invasiveness, TGF- and G protein signaling pathways, DNA damage response pathway, and pathways associated with focal adhesion. Our study revealed a differential pattern of genetic signature in a subgroup of MAC, supporting a genetic influence on corticotrophinomas in patients with CD.
Transcriptome Analysis Showed a Differential Signature between Invasive and Non-invasive Corticotrophinomas.
Sex, Specimen part, Disease
View SamplesLeptospirosis is a neglected zoonotic disease of global importance. Despite its prevalence, pathogenesis is still poorly understood. Our aim was to discover transcripts responsable for pathogenicity of leptospirosis. We compared the transcriptome profiles of saprophyte, attenuated and virulent strain of Leptospira spp.
Transcriptome datasets of macrophages infected with different strains of <i>Leptospira</i> spp.
Cell line
View SamplesTo understand how an inhibition of the mitochondrial ATP synthase affects transcriptional programming and to identify potential candidates of the signaling machinery involved in ATP synthase deficiency responses, we used oligomycin on seedling liquid cultures. Seedlings were harvested at time points 0, 1 and 4 h after the start of oligomycin and control (EtOH) treatments. Already 1 h after addition of oligomycin a total of 102 genes were more than threefold up-regulated and 14 genes were repressed, with most of them showing persistent changes. After 4 h, 580 additional genes were more than threefold up-regulated, and 152 genes were repressed by oligomycin. Several genes for alternative NAD(P)H dehydrogenases and alternative oxidases (AOX1a, AOX1d and NDA1) were up-regulated early, and additional homologs (NDA2, NDB2, NDB4 and AOX1b) followed 4 h after the start of treatment. Several genes for subunits of complex I, complex IV and the ATP synthase were induced whereas hardly any genes encoding enzymes of glycolysis and the TCA cycle changed. Additionally, four of five hallmark genes for oxidative stress were increased by oligomycin. These genes are At2g21640 (UPOX), At1g19020, At1g05340 and At1g57630 and code for proteins of unknown function. Among oxidative stress proteins with known functions, several H2O2-responsive Glutathione-S-transferases and BCS1 (CYTOCHROME BC1 SYNTHESIS) were strongly up-regulated already after 1 h. BCS1 is induced by salicylic acid and independent of other reactive oxygen signaling (ROS) pathways, such as H2O2. The results indicate that several different ROS and defense signaling pathways were induced simultaneously by oligomycin. This is further corroborated by induction of several transcription factors of the WRKY and NAC families, which have been previously implicated in coordinating cellular defense signaling.
Downregulation of the δ-subunit reduces mitochondrial ATP synthase levels, alters respiration, and restricts growth and gametophyte development in Arabidopsis.
Specimen part, Treatment
View SamplesThis study investigated possible molecular changes in the oral mucosa of head and neck squamous cell carcinoma patients submitted to chemoradiotherapy with and without low-level laser therapy by cDNA microarray analysis.
cDNA microarray analysis of human keratinocytes cells of patients submitted to chemoradiotherapy and oral photobiomodulation therapy: pilot study.
Specimen part, Disease, Disease stage
View SamplesBovine leukemia virus (BLV) Tax is a transcriptional activator of viral replication and a key contributor to oncogenic potential. We previously identified interesting mutant forms of Tax with elevated (TaxD247G) or reduced (TaxS240P) transactivation effects on BLV replication and propagation. In this study, to identify genes that play a role in the cascade of signal events regulated by wild-type and mutant Tax proteins, we used a large-scale host cell gene-profiling approach.
Identification of bovine leukemia virus tax function associated with host cell transcription, signaling, stress response and immune response pathway by microarray-based gene expression analysis.
Cell line
View SamplesHuman T cell leukemia virus type 1 (HTLV-1) Tax is potent activator of viral and cellular gene expression that interacts with a number of cellular proteins. In this study, a large-scale host cell signaling events related to cellular proliferation were used to identify genes involved in Tax-mediated cell signaling events related to cellular proliferation and apoptosis.
Visualizing spatiotemporal dynamics of apoptosis after G1 arrest by human T cell leukemia virus type 1 Tax and insights into gene expression changes using microarray-based gene expression analysis.
Cell line
View SamplesPluripotency is the differentiation capacity of particular cells exhibited in the early embryo in vivo and embryonic stem (ES) cells have been shown to originate from the inner cell mass (ICM) of an E3.5 blastocyst. Although the potential for ES cells to differentiate into the three germ layers is equated to ICM cells, they differ in the ability to maintain the capacity for self-renewal. Despite several studies on the maintenance of ES cells in the ground state of pluripotency, the precise mechanism of conversion from the ICM to the ES cell remains unclear. Here , we have examined the cell characteristics and expression profile within the intermediate stages of ES cell derivation from the ICM. Gene clustering and ontology (GO) analyses showed a significant change in the expression of epigenetic modifiers and DNA methylation-related genes in the intermediate stages. We have proposed that an epithelial-to-mesenchymal transition (EMT) blockage is required during derivation of mouse ES cells from E3.5 blastocysts. This study suggests a novel mechanistic insight into ES cell derivation and provides a time-course transcriptome profiling resource for the dissection of gene regulatory networks that underlie the transition from ICM to ES cells.
Blockage of the Epithelial-to-Mesenchymal Transition Is Required for Embryonic Stem Cell Derivation.
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View SamplesThe culture of neural stem cells (NSCs) as floating neurospheres has become widely used as an experimental model to analyse the properties of NSCs. Although the neurosphere model has existed for two decades, there is still no standard protocol to grow NSCs in this way. Thus, we have analysed the consequences of the frequency of growth factor (FGF-2 and EGF) addition to embryonic and adult olfactory bulb stem cells (eOBSCs and aOBSCs) cultures, specifically in terms of proliferation, cell cycle progression, death and differentiation, as well as on global changes in gene expression and signaling pathways. We found that addition of FGF-2 and EGF every two or four days rather than daily significantly reduces the volume of the neurospheres and the total number of cells, changes that were more evident in aOBSC than in eOBSC cultures. The reduction in neurosphere size was mainly due to an increase in cell death and occurs without major changes in the cell cycle parameters tested. Moreover, partial deprivation of FGF-2 and EGF produces a mild increase in aOBSC differentiation during the proliferative phase. Remarkably, these effects were accompanied by a significant upregulation in the expression of genes involved in cell death regulation (Cryab), lipid catabolic processes (Pla2g7), cell adhesion (Dscaml1), cell differentiation (Dscaml1, Gpr17, S100b) and signal transduction (Gpr17, Ndrg2), among others. These findings support that continuous supply of FGF-2 and EGF is critical to maintain the viability/survival of NSCs in culture and reveals novel molecular hallmarks of NSC maintenance/survival and expansion in response to these growth factors.
A global transcriptome analysis reveals molecular hallmarks of neural stem cell death, survival, and differentiation in response to partial FGF-2 and EGF deprivation.
Specimen part
View SamplesAcross life neural stem cells (NSCs) generate new neurons in the mammalian brain through asymmetric neurogenic and self-renewing cell divisions. However, the cellular mechanisms underlying NSC asymmetry remain unknown. Using fluorescence loss in photobleaching (FLIP) we here show that NSCs in vitro and within the developing forebrain generate a lateral diffusion barrier during cell division resulting in asymmetric segregation of cellular components. The strength of the diffusion barrier is dynamically regulated with age and depends on the proper function of lamin-associated nuclear envelope constituents. Strikingly, age-associated or experimental impairment of the diffusion barrier disrupts asymmetric segregation of damaged proteins, a product of aging. Thus, the data presented here identify a mechanism how age is asymmetrically distributed during somatic stem cell division.
A mechanism for the segregation of age in mammalian neural stem cells.
Age, Specimen part
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