Project description:Silicosis, a fibrotic granulomatous lung disease, may occur through accidental high-dose or occupational inhalation of silica, leading to acute/accelerated and chronic silicosis, respectively. While chronic silicosis has a long asymptomatic latency, lung inflammation and apoptosis are hallmarks of acute silicosis. In animal models, histiocytic granulomas develop within days after high-dose intratracheal silica instillation. However, following chronic inhalation of occupationally relevant doses of silica, discrete granulomas resembling human silicosis arise months after the final exposure without significant lung inflammation/apoptosis. To identify molecular events associated with chronic silicosis, lung RNAs from controls or chronically silica-exposed rats were analyzed by Affymetrix at 28 wk after silica exposures. Results suggested a significant upregulation of 144 genes and downregulation of seven genes. The upregulated genes included complement cascade, chemokines/chemokine receptors, G-protein signaling components, metalloproteases, and genes associated with oxidative stress. To examine the kinetics of gene expression relevant to silicosis, qPCR, ELISA, Luminex-bead assays, Western blotting, and/or zymography were performed on lung tissues from 4 d, 28 wk, and intermediate times after chronic silica exposure and compared with 14 d acute silicosis samples. Results indicated that genes regulating fibrosis (secreted phosphoprotein-1, CCL2, and CCL7), redox enzymes (superoxide dismutase-2 and arginase-1), and the enzymatic activities of matrix metalloproteinases 2 and 9 were upregulated in acute and chronic silicosis; however, proinflammatory cytokines were strongly upregulated only in acute silicosis. Thus, inflammatory cytokines are associated with acute but not chronic silicosis; however, genes regulating fibrosis, oxidative stress, and metalloproteases may contribute to both acute and chronic silicosis. 3 rats were chronically exposed to silica by inhalation. Briefly, exposure chambers were maintained with an airflow rate of ~15 cfm and temperature range of 22‚Äì26¬?C. Animals were exposed to 6.2 mg/m3 aerosolized silica (Min-U-Sil 5; U.S. Silica, Mill Creek, OK) with an average particle size of 1.75 ¬± 0.05 mm (mass median aerodynamic diameter) 6 h/d, 5 d/wk (Monday‚ÄìFriday) for 6 wk. 3 control animals received filtered air under similar inhalation conditions.
Project description:Evidence from a few genes of diverse species suggests that marsupial X-chromosome inactivation (XCI) is characterized by exclusive, but leaky, inactivation of the paternally derived X chromosome. To comprehensively study the mechanism of marsupial XCI, we profiled parent-of-origin-specific-allele expression, DNA methylation, and histone modifications in opossum fetal brain and extra-embryonic membranes. The majority (152/176) of X-linked genes exhibited paternally imprinted expression with nearly 100% maternal allele expression, whereas 24 loci (14%) escaped inactivation showing varying levels of biallelic expression. In addition to regulation by the non-coding RSX transcript, strong depletion of H3K27me3 at escaper gene loci indicates that histone states also influence opossum XCI. Notably, the opossum does not show an association between X-linked gene expression and promoter DNA methylation. Our study provides the first comprehensive catalogue of parent-of-origin expression status for X-linked genes in a marsupial and sheds light on the regulation and evolution of imprinted XCI in mammals. Profiling of expression level and allele-specific expression ratios in embryonic day 13 opossum (Monodelphis domestica) fetal brain and extra-embyonic membranes by Illumina RNA-seq
Project description:Transcriptome of D. shibae 5 h in the light after 12 days in co-culture with the dinoflagellate P. minimum. Two biological replicates.
Project description:Sub-thalamic deep brain stimulation (DBS) reversibly modulates ParkinsonM-bM-^@M-^Ys disease (PD) motor symptoms, providing an unusual opportunity to compare leukocyte transcripts in the same subjects before and after neurosurgery and after disconnecting the stimulus (ON-and OFF-stimulus). Here, we report rapid stimulus-induced and largely reversible changes in PD leukocyte transcripts, which were larger in scope than the disease-induced changes. These transcript changes classified advanced pre- from post-surgery PD patients and discriminated patients from controls. Moreover, the extent of changes correlated with the neurological efficacy of the DBS neurosurgery, and covered both regulatory pathways and individual transcript changes, e.g. SNCA, PARK7 and the splicing factor SFRS1. Following 1 hour OFF-stimulus, these changes were largely reversed. We extracted from these differences a modified transcripts signature which discriminated controls from advanced PD patients, pre- from post-surgery and ON-from OFF-stimulus conditions. A further gene-list independent analysis detected reversed pathways. Our findings suggest future uses of this approach and the discovered molecular signature for early diagnostics of PD and for identifying novel targets for therapeutic intervention in this and other DBS-treatable neurological diseases. 27 Total samples were analyzed. Study design included four conditions. PD patients (n=7) leukocyte blood samples were examined at 3 time points, and healthy control subjects (n=6) were examined once each. Samples were taken 1 day prior to sub-thalamic nucleous (STN) DBS treatment, several months after STN-DBS treatment upon optimal stimulation and following one hour electrical stimulation cessation. The off stimulation caused recruitment of the disease symptoms as measured by the Unified Parkinson's Disease Rating Scale motor section (UPDRS-III). The different stages are designated: S1 (pre-treatment), S2 (post STN-DBS) and S3 (upon off stimulation). All patients were on dopamine replacement therapy (DRT) when examined pre- and post-DBS off stimulation (albeit with reduced therapy dose post-DBS). To reduce biological variability among the samples which is not related to the study, only male subjects were included in this study. Samples from six age- and gender- matched healthy control subjects served to detect disease modified transcripts and for pre- and post- treatment comparisons. The study was approved by the human review board at the Hadassah University Hospital, Ein-Kerem (no. 6-07.09.07) in accordance with the Declaration of Helsinki. All study participants signed informed consent.
Project description:We used microarrays to detail the global programme of gene expression underlying the effect of sleep deprivation in the mouse hippocampus and identified distinct classes of regulated genes during this process. Hippocampal tissue was taken from sleep deprived mice and time-matched non-sleep-deprived control animals that were left undisturbed in their home cages during the sleep deprivation period for a total of 8 and 9 replicates per group. RNA was isolated and cDNA was synthesized from hippocampal tissue, and the sample from each animal was hybridized to a separate Affymetrix Mouse 430_2 microarray
Project description:The essential process of dosage compensation equalizes X-chromosome gene expression between C. elegans XO males and XX hermaphrodites through a dosage compensation complex (DCC) that resembles condensin. The DCC binds to both X chromosomes of hermaphrodites to repress transcription by half. Here we show that post-translational modification by the SUMO conjugation pathway is essential for sex-specific assembly of the DCC onto X. Depletion of the SUMO peptide in vivo severely disrupts binding of particular DCC subunits and causes changes in X-linked gene expression similar to those caused by disrupting genes encoding DCC subunits. Three DCC subunits are themselves SUMOylated, and depletion of SUMO preferentially reduces their binding to X, suggesting that SUMOylation of DCC subunits is essential for robust association with X. DCC SUMOylation is triggered by the signal that initiates DCC assembly onto X. The initial step of assembly--binding of X-targeting factors to recruitment sites on X (rex sites)--is independent of SUMOylation, but robust binding of the complete complex requires SUMOylation. SUMOylated DCC subunits are enriched at rex sites, and SUMOylation enhances interactions between X-targeting factors and condensin subunits that facilitate DCC binding beyond the low level achieved without SUMOylation. DCC subunits also participate in condensin complexes essential for chromosome segregation, but their SUMOylation occurs only in the context of the DCC. Our results reinforce a newly emerging theme in which multiple proteins of a complex are SUMOylated in response to a specific stimulus, leading to accelerated complex formation and enhanced function. Total RNA was extracted from mixed stage embryos.
Project description:The SKN-1/Nrf transcription factor family is integral to metabolic homeostasis. There are three SKN-1 isoforms in Caenorhabditis elegans, each with different functions. One of these, SKN-1B, is expressed specifically in neurons and controls hermaphrodite behaviour in response to food. In a laboratory environment C. elegans hermaphrodites must allocate energy efficiently between exploratory food-seeking behaviour, reproduction, and survival, whereas males have to balance both food-seeking with mate-seeking exploratory behaviours. Here, we evaluate the role of SKN-1B in male behaviour and show that SKN-1B acts in a sexually dimorphic manner to control exploratory behaviour, mitochondrial morphology, and mitochondrial function. Moreover, we show that SKN-1B is expressed in a sexually dimorphic pattern, and that SKN-1B influences gene expression on a much broader scale in males compared to hermaphrodites. This analysis identified a neuronal signalling pathway, specifically in males between SKN-1B, the TGF-β ligand DAF-7 and the chemosensory regulator ODR-10, and that this pathway contributes to increased exploratory behaviour in skn-1b mutant males. Taken together our findings identify SKN-1B as a sex-specific neuronal switch to control food searching and mating behaviours. Sexual dimorphism is essential for optimizing survival and reproductive success and our findings establish SKN-1B as a regulator of sex-specific behavioural and metabolic traits. This work provides new insights into neuronal regulation of metabolism and behaviour, with implications for sex-specific physiological adaptations in other species.
Project description:IL-1B is an important cytokine that is often found to be up-regulated during osteoarthritic and rheumatoid joint diseases. It is viewed as a catabolic factor, inducing enzymes that allow for the degradation of the cartilage extracellular matrix and also has essential roles as an autocrine and paracrine factor in fibronectin fragment-mediated degradation. It can also reduce the synthesis of the major cartilage components, type II collagen and aggrecan. On the other hand, IL-1B also has the ability to induce the growth and morphogenic factor BMP-2. During joint diseases, IL-1B is synthesized by both synovial cells and chondrocytes. Addition of IL-1 biological antagonists such as IL-1 receptor antagonists can suppress cartilage degradation in vitro. Thus, the production of IL-1B could act as the first step in mediating a cascade of other mediators in cartilage which could be relevant to the fate of the cartilage. In order to obtain a global picture of the effect of IL-1B production on human adult articular chondrocytes, we analyzed changes in gene expression induced by IL-1B by microarray analysis. We found that IL-1B has a diverse effect on gene expression profile in chondrocytes. One of the predominant responses that we observed in adult human articular chondrocytes on exposure to IL-1B is a dramatic increase in a large set of chemokines and other genes related to the inflammatory cascade. Keywords: Gene response to IL-1B (10 ng/ml) Cartilage was obtained from adult human tissue donors with above the knee amputations due to chondrosarcoma or traumatic injury or from autopsy. Chondrocytes were isolated following established protocols, maintained in high density, and treated with IL-1B (10 ng/ml). Chondrocytes treated with buffer only served as the untreated control. The experiment was carried out in duplicate. Total RNA was extracted from these chondrocytes, labeled with fluorophores (Cy3 or Cy5) and analyzed for expression changes using the Human Operon/Qiagen v3.0 oligonucleotide array. The analysis was repeated with the fluorophore dyes exchanged between the untreated and experimental RNAs.
Project description:Using DNA-microarrays analysis 39 differentially expressed genes were identified in 200 vs. 100 microns biofilms, which might be associated with thickness of S. mutans biofilm. Using DNA-microarrays analysis 29 differentially expressed genes were identified in 400 vs. 100 microns biofilms of S. mutans. 200 vs. 100 microns in depth: The arrays consisted of 1948 70-mer oligonucleotides representing 1960 ORFs from S. mutans UA159 and additional control sequences. The results represent the findings of two independent biological replicate arrays performed with two different RNA samples. In one of the arrays the 100-microns biofilm RNA sample was labeled with Cy5 and the 200-microns biofilm RNA with Cy3, while the second array was reversibly labeled. 400 vs. 100 microns in depth The arrays consisted of 1948 70-mer oligonucleotides representing 1960 ORFs from S. mutans UA159 and additional control sequences. The results represent the findings of three independent biological replicate arrays. In two of the arrays the RNA sample from 100-microns depths biofilm was labeled with Cy5 and the 400-micron - with Cy3, while the third array was reversibly labeled.