ABSTRACT: This SuperSeries is composed of the following subset Series: GSE13980: Analysis of the global gene expression profile for pearl oyster, Pinctada maxima, exposed to organotin (tributyltin) GSE14303: Differential expression analysis of genes from the mantle tissue of pearl oyster: Pinctada maxima GSE14305: The microstructural, mineralogical and transcriptional developments of shell biomineralization of Pinctada maxima Refer to individual Series
Project description:The mantle is a thin tissue from which proteins are secreted dictating the mollusk shell construction. As a conserved organ involved in shell formation throughout mollusks, the mantle is an excellent foundation from which to study biomineralization. A P. maxima mantle tissue specific cDNA microarray, termed PmaxArray 1.0, has been developed comprising 5000 cDNA transcripts derived from the mantle tissue of P. maxima. This tool has been used to investigate the spatial functional dynamics of the mantle tissue identifying over 2000 PmaxArray 1.0 spots as differentially expressed spatially within this organ. Gene expression profiles observed for these transcripts indicated 5 major spatial functions for the mantle, 3 of which have been putatively attributed to shell formation roles associated with nacre microstructure, calcite prismatic microstructure and periostracum. These transcripts are further examined with in situ expression localization and comparative sequence analyses in reference to potential shell formation roles. This spatial investigation has expedited the elucidation of functions within the dynamic mantle organ, paying particular attention to of shell biomineralization. Keywords: Spatial expression profiling by array The mantle tissue from 9 animals was dissected into 5 separate sections: outer fold (OF), middle fold (MF), inner fold (IF), ventral mantle tissue (VM) and dorsal mantle tissue (DM). Total RNA was extracted from these tissues and pooled across subjects in order to reduce the effect of biological variation; such that 3 individuals were pooled together totaling 3 pooled replicate samples for each tissue. All the biologically pooled tissue types were compared against a common reference in which total RNA from all tissues types and all nine animals was equally pooled. A total of 30 dual channel microarrays hybridizations were performed and analyzed.
Project description:Molluscan larval ontogeny is a highly conserved process typical of 3 principal developmental stages. A characteristic unique to each of these stages is shell design, termed prodissoconch I, prodissoconch II and dissoconch. These shells vary in morphology, mineralogy and microstructure. The discrete temporal transitions in shell biomineralization between these larval stages are utilized in this study to investigate transcriptional involvement in several distinct biomineralization events. Scanning electron microscopy and X-ray diffraction analysis of P. maxima larvae and juveniles collected throughout post-embryonic ontogenesis, document the mineralogy and microstructure of each shelled stage as well as establishing a timeline for transitions in biomineralization. P. maxima larval samples most representative of these biomineralization distinctions and transitions were analyzed for differential gene expression on the microarray platform PmaxArray 1.0. A number of transcripts are reported as differentially expressed in correlation to the mineralization events of P. maxima larval ontogeny. Some of those isolated are known shell matrix genes while others are novel, these are discussed in relation to potential shell formation roles. This interdisciplinary investigation has married the shell developments of P. maxima larval ontogeny with corresponding gene expression profiles, furthering the elucidation of shell biomineralization. Keywords: Temporal expression profiling by array Microarray is used to examine the temporal differential expression of transcripts from several bivalve larval development stages including 24hrs post fertilization, 3 days, 17 days, 20 days, 23 days, 26 days, 30 days, 35 days, 40 days. Differential expression profiles for transcripts of all the temporal samples was determined based on comparison to a common reference of unfertilized eggs. Each temporal larval sample included in the study has at least 3 replicate hybridizations. Dye flips have been incorporated in the replicates. A total of 46 microarray hybridizations were performed in this investigation for differential expression analysis.
Project description:Bivalves are well known sentinel organism in the detection of environmental pollutants. Bioaccumulation of these contaminants in bivalves often manifests as specific alterations of their biological processes, which are used as biomarkers for environmental pollution. Tributyltin (TBT) is one such pollutant previously used as a biocide in marine antifouling paints, it now causes a number deleterious effects in bivalves leaching out of sediments in marine ecosystems. One effect extensively documented is shell abnormalities, including shell thickening and chambering. Changes in amino acid compositions of the shell matrix are associated with these deformations suggesting that TBT mode of action influences the biological control of shell biomineralization. This environmental toxicants effect on shell biomineralization was analyzed in this investigation at a transcriptional level in order to elucidate the normal shell biomineralization process. P. maxima animals were exposed to TBT in laboratory conditions and a concentration range for chronic and acute toxicity has been established. Animals exposed to chronic concentrations were analyzed for differential gene expression using PmaxArray 1.0 microarray platform and compared against control animals. Genes indentified as differentially expressed in association with TBT exposure included up-regulation of immunity and detoxification related genes and down-regulation of several shell matrix genes. A number of novel transcripts were additionally identified. The potential actions of these genes are discussed with reference to TBT toxicity and shell biomineralization. This investigation has used a microarray to determine transcriptional effects of TBT on P. maxima and proposed the involvement of novel components in shell formation, aiding the elucidation of the process. Keywords: Expression profiling by array, stress response In order to determine to differential expression profiles for transcripts relevant to TBT exposure, 9 animals treated with TBT 50 ng1-1 were compared to 9 control animals untreated on a dual channel (Cy3 and Cy5) cDNA microarrays. The RNA for the 9 control animals was pooled together for a common reference while the RNA from the 9 treated animals was separated into 3 pooled replicates, each containing RNA from 3 individual animals. Each of the pooled treatment replicates were labeled (Cy3 or Cy5) as was the controls (opposing treatment label) and hybridized to a separate microarray chip, totaling 3 chips. Each chip had duplicate spot grids printed on the left and right of the chip providing technical replication. In total 6 microarrays were challenged and analyzed comprising 3 biological replicates each with 2 technical replicates.
Project description:The simultaneous measurement of gene expression for thousands of genes in a single analysis by the microarray technology allows researchers to describe transcriptomes in various samples of interest. Problems with variation in data quality derived from microarray experiments are well known and might result from poor RNA quality, background problems, or sub optimal signal strength. To assess variation due to the fluorescent dye chosen, three different dye pairs were tested for labelling of cDNA in gene expression analysis experiments on a porcine immune focused oligonucleotide microarray (POM3). This in-house oligonucleotide microarray allowed a direct comparison of background fluorescence, Median signal intensities, numbers of spots detected, and resistance to photobleaching between different dye pairs. We tested Alexa Flour 546/647, Cy3/Cy5 as well as Oyster 550/650 all from Genisphere Inc., Hatfield, PA, USA. Keywords: Comparison of fluorescent dyes Each dye pairs were hybridized on two slides. The same two samples were compared on all the slides used in the present study. The liver sample from a healthy animal was labeled with the high wavelength dyes (Oyster 650/Alexa 647/Cy5) and the liver sample from the sick animal was labeled with the low wavelength dyes (Oyster 550/Alexa 546/Cy3). Each slide was scanned 3 times, immediately after hybridization (first round), after 1 month of storage in darkness and after 24 hours on the bench (12 hours of daylight and 12 hours of artificial light). Total RNA from the infected and control liver samples were extracted using RNeasy midi kit (Qiagen, Denmark) and DNase treated using RNase-Free DNase Set (Qiagen). 3DNATM Array 900 expression array detection kits (Genisphere Inc.) were used for the labeling and cDNA synthesis reaction of the RNA in the present study. Three different pairs of fluorescent dyes Oyster 550/650 (Genisphere Inc.), Alexa 546/647 (Genisphere Inc.), and Cy3/Cy5 (Genisphere Inc.) were used in separate labeling reactions. Labeling was done according to the manufacturers protocol for large-scale cDNA synthesis. For the cDNA synthesis 9.2µg total RNA from each liver sample was used and mixed with 20U AmpliQ RTenzyme and 10x first strand buffer (Bie og Berntsen, Rødovre, Denmark). Hybridization and washing were performed according to the manufacturers instructions (Genisphere) using Corning hybridization chambers. For one cDNA hybridization reaction; 6.5µl cDNA from each synthesis, 0.5µl Salmon sperm (10µg/µl) and 13.5µl 2 x Formamide-Based Hybridization Buffer (3DNA Array 900, Genisphere) was used. A total hybridization mix of 29µl was applied under a 22I x 25 mm LifterSlip (Erie Scientific, Portsmouth, NH, USA) carefully avoiding air bubbles. Slides were incubated at 44oC in a water bath over night. Wash buffer 1 (3DNA Array 900, Genisphere) was preheated to 44oC for the post cDNA hybridization wash. For two 3DNA hybridization reaction mixes; 2.5µl of each Capture reagent and 26µl SDS-Based hybridization buffer was mixed to a final volume of 52µl. 26µl 3DNA hybridization mix was applied to each slide, and incubated in darkness in a water bath at 50oC for 4 hours. Wash buffer 1 was preheated to 60oC for the post 3DNA hybridization wash. Slides were scanned on a CCD ArrayWoRxe auto (Applied Precision, Issaquah, WA, USA) using different exposure times (0.3 for 595 nm and 1.2 for 685 nm).
Project description:A continuous culture of Bifidobacterium longum NCC2705 was carried out in a 2.5-l reactor (Bioengineering AG, Wald, Switzerland), equipped with a Biospectra control system (Biospectra AG, Schlieren, Switzerland) and containing 2 l of MRS, added of 0.05% cysteine, inoculated with 2 % (v/v) preculture. The temperature was maintained at 37°C and the pH at 6.0 by addition of 5 M NaOH. The culture was stirred constantly at 250 rpm using two rushton type propellers. Anaerobic conditions were maintained by flushing the headspace of the reactor with CO2. After 8 h in batch mode the culture was run in continuous mode at a dilution rate of 0.1 h-1. Fresh medium was added using a peristaltic pump (Alitea, Bioengineering AG, Wald, Switzerland), and fermented broth harvested with a second peristaltic pump (Alitea, Bioengineering AG, Wald, Switzerland) set at a slightly higher flow rate. A stabilization period of 90 h (corresponding to nine reactor volume changes) was operated prior culture monitoring (t=0). Aliquots of 2 ml taken at t=31, 134 and 211 h were centrifuged (4,000 g, 1 min, room temperature) for transcriptomic analysis. Supernatants were discarded and cell pellets snap frozen in liquid nitrogen and stored at -80ºC until RNA-extraction. Keywords: Time course of Bifidobacterium longum in continuous culture Bifidobacterium longum NCC2705 at time 31 versus time 134 h and versus time 211 h in continuous culture. Two technical replicares with dyes swaps
Project description:Transcriptional profiling of Bifidobacterium longum mutant versus wt strain in exponentional phase Keywords: Characterization of natural mutant One B. longum mutant (HPR2) was analysed versus the wt strain NCC2705 in: exponential phase 37°,pH 6.0, MRS, headspace flushing with CO2. Three biological replicates.
Project description:This SuperSeries is composed of the following subset Series: GSE10413: Gene expression profiling of caffeic acid phenethyl ester-treated human umbilical vein endothelial cells-1 GSE10429: Gene expression profiling of caffeic acid phenethyl ester -treated human umbilical vein endothelial cells-2 Keywords: SuperSeries Refer to individual Series
Project description:Caffeic acid phenethyl ester (CAPE), derived from various plant sources, has been shown to ameliorate ischemia/reperfusion (I/R) injury in vivo, and this has been attributed to its ability to reduce the oxidative stress. Here we investigated the cytoprotection of CAPE against menadione (MD)-induced oxidative stress in human umbilical vein endothelial cells (HUVEC) to evaluate potential gene expression involvement. CAPE exhibited dose-dependent cytoprotection of HUVEC that required preincubation. A gene screen with microarrays was performed to identify the potential cytoprotective gene(s) induced by CAPE. Heme oxygenase-1 (HO-1) was highly upregulated by CAPE and this was confirmed with reverse transcriptase polymerase chain reaction (RT-PCR) and western blotting. Keywords: gene expression in HUVEC, CAPE cytoprotective dose response Confluent HUVEC were incubated with cytoprotective dose of CAPE at 5 µg/ml or 0.1% DMSO as vehicle control for 6 hrs. Both treatments were done in triplicates. Total RNA was isolated at the end of the treatment and applied to microarray experiments in order to identify transcriptional response of HUVEC to CAPE. Microarray experiments were based on a two-color reference design using human universal reference RNA to compare results bwtween CAPE treatment and vehicle control groups.
Project description:Transcriptional profiling of Bifidobacterium longum mutants versus wt strain in exponentional phase, with or without heat-shock treatment, and in stationary phase Keywords: Characterization of natural mutants Two B. longum mutants (NCC2912 and NCC2913) were analysed versus the wt strain NCC2705 in three conditions : exponential phase 37°, exponential phase with 7 min 50° heat shock, stationary phase. Two biologic replicates and 2 technical replicates
Project description:Caffeic acid phenethyl ester (CAPE), derived from various plant sources, has been shown to ameliorate ischemia/reperfusion (I/R) injury in vivo, and this has been attributed to its ability to reduce the oxidative stress. Here we investigated the cytoprotection of CAPE against menadione (MD)-induced oxidative stress in human umbilical vein endothelial cells (HUVEC) to evaluate potential gene expression involvement. CAPE exhibited dose-dependent cytoprotection of HUVEC that required preincubation. A gene screen with microarrays was performed to identify the potential cytoprotective gene(s) induced by CAPE. Heme oxygenase-1 (HO-1) was highly upregulated by CAPE and this was confirmed with reverse transcriptase polymerase chain reaction (RT-PCR) and western blotting. Keywords: Gene expression in HUVEC, CAPE cytoprotective dose response Confluent HUVEC were incubated with cytoprotective dose of CAPE at 5 µg/ml or 0.1% DMSO as vehicle control for 6 hrs. Both treatments were done in triplicates. Total RNA was isolated at the end of the treatment and applied to microarray experiments in order to identify transcriptional response of HUVEC to CAPE. Microarray experiments were based on a two-color reference design using human universal reference RNA to compare results bwtween CAPE treatment and vehicle control groups.