Project description:We report RNA-Seq experiments of whole eye tissues from A/J, BALB/c, and C57BL/6 background mice. Examine ocular tissue from 3 different background mice that display varying rates of retinal degeneration.
Project description:We report RNA-Seq experiments of whole eye tissues from C57BL/6J background mice at 1.5 h and 9.0 h after light onset to better understand photoreceptor phagocytosis Examine ocular tissue from mice at different time points
Project description:We report RNAseq analysis of the transcriptome of retinas from mature rod-specific Dicer1 cKO mice and control littermates lacking Cre expression in order to better understand changes in gene regulation that could lead to retinal degeneration in cKO mice. Examine retinal transcriptome of 3 biological replicates for each genotype from 4-week-old animals with tissue collected between 8:00 - 10:00AM
Project description:We report RNAseq analysis of the transcriptome of 3 biological replicates of bovine retina Examine retinal transcriptome of 3 biological replicates with tissue collected between 7:00 - 10:00AM
Project description:The initial aim of this work was to understand the pathophysiology of Enhanced S-cone Syndrome (ESCS) that leads to retinal degeneration. Although ESCS was identified in humans decades ago and since then the causative genes have been elucidated, our understanding of the accompanying retinal degeneration is still poorly understood. Knockout of the Nrl transcription factor in mice produces a retina overpopulated with S-cone like photoreceptors along with absence of rod photoreceptors and recapitulates many of the phenotypic features seen in human ESCS patients. We wanted to study this murine model through a combinatorial genetic and structural approach to improve understanding of the disease process that leads to photoreceptor degeneration and blindness, potentially guiding future therapies. By using RNA-Sequencing (RNA-Seq) to examine mature wild type and Nrl-/- ocular tissues, we were able to determine global changes in their transcriptomes. The massively parallel RNA-sequencing experiment revealed new insight into the transcriptional mis-regulation in the ESCS murine model and revealed a change in gene expression in putative proteins involved in photoreceptor phagocytosis. Key photoreceptor ligands necessary for phagocyotsis, Tub and Tulp1, were down-regulated in the Nrl-/- retina. Down regulation of key retinoid metabolic genes, coupled with down-regulation of Tub and Tulp1, suggested a potential mechanism involving defective phagocytosis underlies the photoreceptor degeneration seen in ESCS. We report RNA-Seq experiments of whole eye and retinal tissues from wild type and Nrl transcription factor knockout mice on the C57BL/6 background. Examine two different ocular tissues in two mouse models of varying photoreceptor populations
Project description:DNA from expanded bovine blastocysts and bovine sperm were extracted then subjected to methylation-sensitive enzymatic digestion and LM-PCR enrichment before being hybridized onto a microarray. Two-condition experiment, bovine blastocysts (pools of 10) vs bovine sperm. Four biological replicates of each tissue were hybridized to four two-color arrays in a dye-balanced design.
Project description:Aquatic ecosystems are subjected to a variety of man-induced stressors but also vary spatially and temporally due to variation in natural factors. In such complex environments, it remains difficult for ecotoxicologists to evaluate the effects of contaminants in wild organisms. The aim of the present study was to test the possibility to detect and unravel the effects of different anthropogenic and natural factors on wild fish by the use of a DNA microarray. Transcriptomic profiles from laboratory-exposed and wild fish sampled along a contamination gradient were compared. During laboratory experiments, fish were exposed to pollutants or natural factors under levels that were closed to those found in the sampling sites. A strong difference was observed between the transcriptomic patterns of wild and laboratory-exposed animals, suggesting a general stress induced by captivity in laboratory. Surprisingly, animals acclimatized to cold temperature clustered with fish from the most contaminated sites and shared common genes involved notably in epigenetic mechanisms. A possible energy saving strategy was suggested in cold-acclimated animals. This result may suggest that animals chronically exposed to contaminants develop a general defense/adaptation strategy against pollution through a general shunt in their basal metabolism, whatever the type of contaminants. 84 samples were analyzed from wild and laboratory animals (5 individuals per condition or sampling site). Seven sampling wild sites were selected in Canada (St. Jean, Sud-Ouest, St. FranM-CM-'ois, St. Pierre) and in France (Dordogne, Garonne, Gironde) on the basis of their known gradient of contamination by metallic and organic pollutants previously described in Baillon et al., in press. Each sample were hybridized with a same reference on array (30 samples from reference site (Certes, France) collected in spring 2011 and 2012. Animals from laboratory exposures were described below.
Project description:The response regulator RpaA is required for control of genome-wide gene expression by the cyanobacterial circadian clock. RpaA is predicted to be a DNA binding protein based on sequence homology, but prior studies have been unable to detect binding in vitro or in vivo to a small panel of promoters. We used ChIP-Seq to determine whether RpaA associates with DNA in vivo, and if so, with what dynamics. We find that RpaA binds to over 100 location in the genome in a circadian manner, with strongest binding occuring around subjective dusk. Analysis of these binding sites shows that RpaA directly regulates the expression of clock components to generate feedback on the core oscillator, and also regulates expression of a small set of circadian effectors that in turn orchestrate global expression rhythms. Crosslinked samples were acquired every four hours from a turbidostatic wild-type (AMC408) cultures in constant light (LL) following entrainment with two light-dark (LD) cycles. As a negative control, we acquired samples similarly from an M-NM-^TrpaA culture. Chromatin immunoprecipitation was performed on each sample from wht wild-type and from a pool of all samples from the M-NM-^TrpaA culture. Libraries were prepared from the ChIP samples and sequenced with Illumina technology. For the wild-type, biological replicate samples were acquired at times of maximum and minimum RpaA binding.
Project description:The efficacy of inoculation of single pure bacterial cultures into complex microbiomes, for example, in order to achieve increased pollutant degradation rates in contaminated material (i.e., bioaugmentation), has been frustrated by insufficient knowledge on the behaviour of the inoculated bacteria under the specific abiotic and biotic boundary conditions. Here we present a comprehensive analysis of global gene expression of the bacterium Sphingomonas wittichii RW1 in contaminated sand, compared to regular suspended batch growth in liquid culture. RW1 is a well-known bacterium capable of mineralizing polycyclic aromatic hydrocarbons such as dioxins, dibenzofurans and other chlorinated congeners. We tested the reactions of the cells both during the immediate transition phase from liquid culture to sand with or without dibenzofuran, as well during growth and stationary phase in sand. Cells during transition resemble going through stationary phase, showing evidence of stress responses and nutrient scavenging, and even of major adjustments in their primary metabolism if they were not pre-cultured on the same contaminant as found in the soil. Cells growing and surviving in soil show very different signatures as in liquid or in liquid culture exposed to chemicals inducing drought stress, and we obtain evidence for numerous soil-specific expressed genes. We conclude that studies focusing on inoculation efficacy should test behavior under conditions as closely as possible mimicking the intended microbiome conditions We were interested to study the global reactions of bacteria with biodegradative properties under near-environmental as compared to laboratory culture conditions. we compared here the genome-wide responses of RW1 between regular laboratory batch growth on the aromatic substrates DBF and salicylate with growth in sandy soil with or without the same aromatic compounds. We analysed the cellular reactions immediately after introduction into the sand, during lag phase, all in carefully controlled and replicated experimental conditions.