This study was designed to provide a genome-wide analysis of the effects of luteinizing hormone (LH) ablation/replacement versus steroid ablation/replacement on gene expression in the developed corpus luteum (CL) in primates during the menstrual cycle. Naturally cycling, female rhesus monkeys were left untreated (Control; n = 4) or received one of the following treatments for three days beginning on Day 9 of the luteal phase: daily injection of the gonadotropin-releasing hormone (GnRH) antagonist (Antide; n = 5), Antide + recombinant human LH (A+LH; n = 4), Antide + LH + the 3b-HSD antagonist Trilostane (A+LH+TRL; n = 4), and Antide + LH + TRL + progesterone replacement with a synthetic progestin R5020 (A+LH+TRL+ R5020; n = 5). On Day 12 of the luteal phase, CL were removed and samples of RNA from individual CL were fluorescently labeled and hybridized to Affymetrix rhesus macaque total genome microarrays. The greatest number of altered transcripts was associated with the ablation/replacement of LH, while ablation/replacement of progestin affected fewer transcripts. Replacement of LH during Antide treatment restored expression of most transcripts to control levels. Real-time PCR validation of a subset of transcripts revealed that most expression patterns were similar between microarray and real-time PCR. Analysis of protein levels were subsequently determined for 2 of the transcripts differentially expressed by real-time PCR. This is the first genome-wide analysis of LH and steroid regulation of gene transcription in the developed primate CL. Further analysis of novel transcripts identified in this data set can clarify the relative role for LH and steroids in CL maintenance and luteolysis.
The effects of luteinizing hormone ablation/replacement versus steroid ablation/replacement on gene expression in the primate corpus luteum.
No sample metadata fields
View SamplesTo obtain a genomic view of hepatocyte nuclear factor-4 (HNF-4) in the regulation of the inflammatory response, microarray analysis was used to probe the expression profile of an inflammatory response induced by cytokines in a model of knock-down HNF-4 HepG2 cells. The results indicate an extensive role for HNF-4 plays in the regulation of a large number of the liver-specific genes. Majority of genes (71%) affected by cytokine treatment are also affected by HNF-4 knock-down. This significant overlap suggests that HNF-4 may play a role in regulating the cytokine-induced inflammatory response.
Expression profile analysis of the inflammatory response regulated by hepatocyte nuclear factor 4α.
No sample metadata fields
View SamplesTo explore chorionic gonadotropin (CG)-regulated gene expression in the primate corpus luteum (CL), adult female rhesus macaques were treated with a model of simulated early pregnancy (SEP). Total RNA was isolated from individual CL and hybridized to Affymetrix GeneChip Rhesus Macaque Genome Arrays The level of 1192 transcripts changed expression > 2-fold (one-way ANOVA, FDR correction; P<0.05) during SEP when compared to Day 10 untreated controls, and the majority of changes occurred between Days 10 and 12 of SEP. To compare transcript levels between SEP rescued and regressing CL, previously banked rhesus GeneChip array data from the mid- to late and very late luteal phase were analyzed with time-matched intervals in SEP. Comparing RMA-normalized transcripts from the natural cycle with those from luteal rescue revealed 7677 transcripts changing in expression pattern >2 fold (one-way ANOVA, FDR correction; P<0.05) between the two groups. Clustering of samples revealed that the SEP samples possessed the most related transcript expression profiles. Regressed CL (days 18-19, around menses) were the most unlike all other CL. The most affected KEGG pathway was Steroid Biosynthesis, and most significantly absent pathways following SEP treatment includes groups of genes whose products promote cell-death. By further comparing the genome-wide changes in luteal gene expression during rescue in SEP, with those in CL during luteolysis in the natural menstrual cycle, it is possible to identify key regulatory pathways promoting fertility.
Microarray analysis of the primate luteal transcriptome during chorionic gonadotrophin administration simulating early pregnancy.
Sex, Specimen part
View SamplesThe LH-like molecule chorionic gonadotropin (CG) is secreted by the macaque conceptus during and following implantation, rescuing the CL from impending regression and extending its functional lifespan in early pregnancy for approximately two weeks. CG binds to the same receptor as LH; i.e., LHCGR, and promotes production of steroids and other factors such as relaxin (RLN1). Our research group recently used Affymetrix rhesus macaque total genome arrays to compare the effects of CG on the luteal transcriptome from rhesus females during simulated early pregnancy (SEP) with changes during luteal regression in the non-fecund menstrual cycle. This analysis demonstrated that CG-rescue affected expression levels of 4,500 mRNA transcripts between days 10 and 15 of the luteal phase. Previous analyses indicated that a portion of the transcriptome in the macaque CL of the menstrual cycle was regulated indirectly by LH via the local actions of steroid hormones, including progesterone (P). Therefore, this study was designed to distinguish CG-regulated luteal genes that are dependent versus independent of local steroid (P) action. A protocol of increasing dosages of hCG (SEP) was begun on day 9 of the luteal phase in rhesus females combined with concurrent administration of the 3BHSD inhibitor trilostane (TRL) +/- the synthetic progestin (P) R5020. CL were collected on day 10 (no treatment) of the luteal phase to serve as a baseline comparison (n=8), 1 day of SEP (Day 10+hCG+/-TRL+/-R5020) and 6 days of SEP (Day 15+hCG+/-TRL+/-R5020); n=4/group. In the presence of CG, treatment with TRL reduced serum P levels to less than 1 ng/ ml after 1 day and all of the Day 15+h+TRL-treated females initiated menses before CL collection. The isolated CL were processed for total RNA and hybridized to microarrays. Compared to hCG treatment alone, 50 significantly altered mRNA transcripts were identified on day 10, rising to 95 on day 15 (P<0.05, 2-fold change in gene expression). The mRNA levels for several genes were validated in CL by real-time PCR. RNL1 levels increased with CG-treatment, but were not affected by steroid ablation, similar to previously reported relaxin protein expression. Steroid-sensitive genes included CDH11, IL1RN, INSL3, LDLR, OPA1, SERPINE1, SFRP4, and TNSF13B1; however differential sensitivity was observed and effects of steroid ablation and P replacement varied by day. Expression of some genes (e.g., 3BHSD2, ADAMTS1, ADAMTS5, MMP9, STAR, and VEGFA) previously identified as steroid regulated in the macaque CL during the menstrual cycle were not significantly altered by steroid ablation and P replacement during CG exposure in SEP. These data indicate that the majority of CG-regulated luteal transcripts are differentially expressed independently of local steroid actions. The proportion of steroid sensitive mRNA transcripts in the presence of CG is much smaller than in the presence of LH during the non-fecund cycle. Nevertheless, the steroid-regulated genes in the macaque CL may be essential during early pregnancy, based on the previous report that TRL treatment initiates premature structural regression of the CL during SEP. These data reinforce the concept that the structure, function, and regulation of the rescued CL in early pregnancy is different from the CL of the menstrual cycle.
Effects of steroid ablation and progestin replacement on the transcriptome of the primate corpus luteum during simulated early pregnancy.
Sex, Specimen part
View SamplesWe report the effect of DKK1 treatment during culture on the length and transcriptome of embryos on day 15 of development, supporting the notion that changes early in development affect later stages of development. Overall design: Bovine embryos were produced in vitro and exposed to either 0 or 100 ng/ml DKK1 from day 5 to 7 of culture. Embryos were transferred on day 7 and recovered on day 15 for evaluation of length and transciptome
Dickkopf-related protein 1 is a progestomedin acting on the bovine embryo during the morula-to-blastocyst transition to program trophoblast elongation.
Treatment, Subject
View SamplesThe accumulation of unfolded proteins in the lumen of the endoplasmic reticulum (ER) causes stress and induces the unfolded protein response (UPR) which is characterised in part by the transcriptional induction of genes involved in assisting protein folding. Translational responses to ER stress have been less well described and here we report on a genome-wide analysis of translational regulation in the response to the ER stress-inducing agent dithiothreitol (DTT) in Saccharomyces cerevisiae. Although the observed polysome profiles were similar under control and ER stress conditions microarray analysis identified transcipt-specific translational regulation. Genes with functions in ribosomal biogenesis and assembly were translationally repressed under ER stress. In contrast mRNAs for known UPR genes, including the UPR transcription factor HAC1, the ER-oxidoreductase ERO1 and the ER-associated protein degradation (ERAD) gene DER1 were enriched in polysomal fractions under ER stress conditions. In addition, we show that splicing of HAC1 mRNA is required for efficient ribosomal loading and that Gcn2p is required for normal HAC1 splicing, so shedding light on the role of this protein kinase in the UPR pathway.
Transcript-specific translational regulation in the unfolded protein response of Saccharomyces cerevisiae.
No sample metadata fields
View SamplesMSL (Male-specific lethal) complex increases transcription on the single X chromosome of Drosophila males in order to equalize expression of X-linked genes between males (XY) and females (XX). The increase in transcript levels correlates with MSL- dependent acetylation of histone H4 at K16 within the bodies of active genes, but identification of the transcriptional step affected has not been possible. In this study, we use global run-on sequencing (GRO-seq) to examine the specific effect of MSL complex on RNA Polymerase II (RNAP II) on a genome-wide level. Results indicate that MSL complex enhances transcription by facilitating the progression of RNAP II across the bodies of active X-linked genes. Improving transcriptional output downstream of typical gene-specific control may explain how dosage compensation can be imposed on the diverse set of genes along an entire chromosome. Overall design: Global Run-On Sequencing (GRO-Seq) reads, i.e., RNA-Seq of nascent RNA transcripts, from D. Melanogaster SL2 cells. Two biological replicates of cells treated with control GFP RNAi and cells treated with MSL2 RNAi were analyzed.
X chromosome dosage compensation via enhanced transcriptional elongation in Drosophila.
Subject
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Combined Gene Expression and RNAi Screening to Identify Alkylation Damage Survival Pathways from Fly to Human.
Specimen part, Treatment
View SamplesDespite the high toxicity, alkylating agents are still at the forefront of several clinical protocols used to treat cancers. In this study, we investigated the mechanisms underlying alkylation damage responses, aiming to identify novel strategies to augment alkylating therapy efficacy. In this pursuit, we compared gene expression profiles of evolutionary distant cell types (D. melanogaster Kc167 cells, mouse embryonic fibroblasts and human cancer cells) in response to the alkylating agent methyl-methanesulfonate (MMS). We found that many responses to alkylation damage are conserved across species independent on their tumor/normal phenotypes. Key amongst these observations was the protective role of NRF2-induced GSH production primarily regulating GSH pools essential for MMS detoxification but also controlling activation of unfolded protein response (UPR) needed for mounting survival responses across species. An interesting finding emerged from a non-conserved mammalian-specific induction of mitogen activated protein kinase (MAPK)-dependent inflammatory responses following alkylation, which was not directly related to cell survival but stimulated the production of a pro-inflammatory, invasive and angiogenic secretome in cancer cells. Appropriate blocking of this inflammatory component blocked the invasive phenotype and angiogenesis in vitro and facilitated a controlled tumor killing by alkylation in vivo through inhibition of alkylation-induced angiogenic response, and induction of tumor healing.
Combined Gene Expression and RNAi Screening to Identify Alkylation Damage Survival Pathways from Fly to Human.
Specimen part, Treatment
View SamplesDespite the high toxicity, alkylating agents are still at the forefront of several clinical protocols used to treat cancers. In this study, we investigated the mechanisms underlying alkylation damage responses, aiming to identify novel strategies to augment alkylating therapy efficacy. In this pursuit, we compared gene expression profiles of evolutionary distant cell types (D. melanogaster Kc167 cells, mouse embryonic fibroblasts and human cancer cells) in response to the alkylating agent methyl-methanesulfonate (MMS). We found that many responses to alkylation damage are conserved across species independent on their tumor/normal phenotypes. Key amongst these observations was the protective role of NRF2-induced GSH production primarily regulating GSH pools essential for MMS detoxification but also controlling activation of unfolded protein response (UPR) needed for mounting survival responses across species. An interesting finding emerged from a non-conserved mammalian-specific induction of mitogen activated protein kinase (MAPK)-dependent inflammatory responses following alkylation, which was not directly related to cell survival but stimulated the production of a pro-inflammatory, invasive and angiogenic secretome in cancer cells. Appropriate blocking of this inflammatory component blocked the invasive phenotype and angiogenesis in vitro and facilitated a controlled tumor killing by alkylation in vivo through inhibition of alkylation-induced angiogenic response, and induction of tumor healing.
Combined Gene Expression and RNAi Screening to Identify Alkylation Damage Survival Pathways from Fly to Human.
Specimen part, Treatment
View Samples