Nitric oxide and NO-derived species (RNS) are defense molecules with broad antimicrobial activity. Micro-organisms have developed strategies to sense RNS and counteract their damaging effects. We used Saccharomyces cerevisiae, harbouring a deletion of YHB1 that encodes the main NO scavenger enzyme, to study consequences of RNS exposure on whole genome transcriptional response. The expression of >700 genes was altered on RNS treatment. No major role for ROS-scavenging enzymes was found, and the respiratory chain, the main site of ROS production, had only minor involvement in the RNS-induced stress. The changes were generally transient and also found after treatment with the respiratory inhibitor myxothiazol. 117 genes however showed a persistent response which was not observed after myxothiazol treatment. Of these, genes of the glutathione and DNA repair systems, iron homeostasis and transport were found up-regulated. Severe repression of genes of respiratory chain enzymes was observed. Many of these genes are known to be regulated by the transcription factor Hap1p suggesting that RNS might interfere with Hap1p activity. We showed also that Msn2/4p and Yap1p, key regulators of the response to, respectively, general stress and oxidative stress, played a role in mediating the RNS-induced response.
Transcriptional response to nitrosative stress in Saccharomyces cerevisiae.
Compound, Time
View SamplesInfluence of ovarian stimulation with 200 IU of hCG, (administered in the late follicular phase among ICSI patients undergoing a GnRH-antagonist protocol), on the endometrium on the day of oocyte pick-up.
Gene expression profile in the endometrium on the day of oocyte retrieval after ovarian stimulation with low-dose hCG in the follicular phase.
Specimen part, Treatment
View SamplesThe mitochondrial respiratory chain is composed of lipoprotein complexes imbedded in the inner mitochondrial membrane. This chain of enzymes transfers electrons from NADH and FADH2, provided from divers metabolic pathways, to oxygen. It couples the transfer of electrons to the translocation of protons across the membrane. Several clinical syndromes have been associated with respiratory dysfunction caused by mitochondrial or nuclear mutations. A number of mutations in the mitochondrial genes encoding for cytochrome b (CYTB) and cytochrome oxidase (COX 1, 2 and 3) have been linked with diseases. We are using yeast mutants to characterize the deleterious effect of mutations reported in patients on the assembly and catalytic properties of the affected enzymes, and to study the impact of mutations in nuclear genes, such as OXA1, encoding for factors required for the assembly of the respiratory complexes. In this work, we monitored the effects of the mutations causing respiratory defect on the whole genome expression. We compared the change in gene expression in rho0 cells (with a complete deletion of the mitochondrial genome, and by consequence without respiratory chain), in cells with either a single defective enzyme or several, and in cells after prolonged treatment with the bc1 inhibitors myxothiazol or antimycin. The impact of the mutations on the respiratory function ranged from mild to severe. The expression of approx. 350 genes was changed in at least one mutant. Cluster analysis was performed using the Cluster program (Eisen, 1998, PNAS 95:14863). Four groups of genes were studied in more details: Group A, the most repressed genes; Group B, the most over-expressed genes; Group C, genes more repressed in rho0 and Doxa1 cells; and Group D, genes more over-expressed in Doxa1.
Multiple defects in the respiratory chain lead to the repression of genes encoding components of the respiratory chain and TCA cycle enzymes.
Compound
View SamplesIn GnRH-antagonist/rec-FSH stimulated cycles, advanced endometrial maturation on the day of oocyte retrieval correlates with altered gene expression
In GnRH antagonist/rec-FSH stimulated cycles, advanced endometrial maturation on the day of oocyte retrieval correlates with altered gene expression.
No sample metadata fields
View SamplesPremature progesterone (P) rise during GnRH antagonist cycles for IVF is a frequent phenomenon and has been associated with lower pregnancy and implantation rates. Different thresholds of progesterone have been used so far to define its premature rise during the follicular phase of an IVF stimulated cycle. In this study, we evaluated endometrial gene expression on the day of oocyte retrieval according to the level of serum progesterone on the day of hCG administration in GnRH antagonist cycles.Endometrial biopsies from eleven patients were taken with a Pipelle de Cornier (Prodimed, Neuilly-en-Thelle, France) on the day of oocyte retrieval in a GnRH antagonist/rec-FSH stimulated IVF cycle with fresh embryo transfer. Biopsies were analysed for gene expression with Affymetrix Human Genome (HG) U133 Plus 2.0 Arrays and GCOS software (Affymetrix, Santa Clara, CA, USA). Patients were divided into three different groups according to their progesterone serum concentration on the day of hCG administration (A) P <= 0.9 ng/mL, (B) 1 < P < 1.5 ng/mL, and (C) P > 1.5 ng/mL. Serum P was measured with the automated Elecsys immunoanalyser (Roche Diagnostics, Mannheim, Germany). Selected differentially expressed genes were validated with quantitative real-time PCR (QPCR) with TaqMan Gene Expression Assays (Applied Biosystems, Foster City, CA, USA).
Progesterone rise on HCG day in GnRH antagonist/rFSH stimulated cycles affects endometrial gene expression.
Specimen part
View SamplesCONTEXT Nowadays, the molecular mechanisms involved in endometrial receptivity and implantation are still not clear.
Cyclooxygenase-2 network as predictive molecular marker for clinical pregnancy in in vitro fertilization.
No sample metadata fields
View SamplesInfluence of ovarian stimulation with 200 IU of hCG, (administered in the late follicular phase among ICSI patients undergoing a GnRH-antagonist protocol), on the endometrium on the day of oocyte pick-up.
Cyclooxygenase-2 network as predictive molecular marker for clinical pregnancy in in vitro fertilization.
Specimen part
View SamplesEffect of absence of interaction with MHC class II on memory CD4 T cells
Noncognate interaction with MHC class II molecules is essential for maintenance of T cell metabolism to establish optimal memory CD4 T cell function.
Sex, Specimen part
View SamplesTransgenic mice were generated that expressed the inhibitor of apoptosis and mitotic regulator survivin in pancreatic islet beta cells. Control non-transgenic or transgenic islets were then used in a model of islet transplantation in diabetic recipient mice and tested for their ability to correct hyperglycemia and allow long-term engraftment of tranplanted islets in vivo. Control or transgenic islets were analyzed by chip microarray for potential transcriptional changes associated with transgenic expression of survivin, in vivo.
Genome-wide analysis of Polycomb targets in Drosophila melanogaster.
Sex, Age, Specimen part
View SamplesIn order to investigate the impact of MMP-14 (MT1-MMP) and three-dimensional (3D) culture conditions on the transcriptomes of a human breast adenocarcinoma cell line, we performed a microarray analysis from RNAs isolated from MCF-7 cells expressing either an empty vector (CTRL) or human MMP-14 cDNA (MT1) in monolayer (2D) and 3D collagen (3D Col) growth conditions.
A membrane-type-1 matrix metalloproteinase (MT1-MMP)-discoidin domain receptor 1 axis regulates collagen-induced apoptosis in breast cancer cells.
Cell line
View Samples