Project description:To investigate response or resistance to endocrine therapy, mice with targeted over-expression of Esr1 or CYP19A1 to mammary epithelial cells were employed, representing two direct pathophysiological interventions in estrogen pathway signaling. Both Esr1 and CYP19A1 over-expressing mice responded to letrozole with reduced HAN prevalence and decreased mammary epithelial cell proliferation. CYP19A1 over-expressing mice were tamoxifen-sensitive but Esr1 over-expressing mice were tamoxifen-resistant. Increased ER expression occurred with tamoxifen resistance but no consistent changes in progesterone receptor, pSTAT3, pSTAT5, cyclin D1 or cyclin E levels in association with response or resistance was found. RNA-seq was employed to seek a transcriptome predictive of tamoxifen resistance using these models and a second tamoxifen-resistant model, BRCA1 deficient/Trp53 haploinsufficient mice. Sixty-eight genes associated with immune system processing were upregulated in tamoxifen-resistant Esr1 and Brca1 deficient mice whereas genes related to aromatic compound metabolic process were upregulated in tamoxifen-sensitive CYP19A1 mice. Interferon Regulatory Factor 7 was identified as a key transcription factor regulating these 68 immune processing genes. Two loci encoding novel transcripts with high homology to human IGLL1 were uniquely upregulated in the tamoxifen-resistant models. Letrozole proved to be a successful alternative to tamoxifen. Further study of transcriptional changes associated with tamoxifen resistance including immune-related genes could expand our mechanistic understanding and lead to biomarkers predictive of escape or response to endocrine therapies. Single- and paired-end mRNA-seq with WT, Esr1 over-expressing (CERM, tetracycline-operator(tet-op)-Esr1MMTV-rtTA), CYP19A1 over-expressing (AROM, tet-op-CYP19A1MMTV-rtTA) and Brca1 KO (BRCA, Brca1fl11/fl11/MMTV-Cre/p53+/- ) mice
Project description:Intracellular calcium levels are finely tuned through intricate actions of a number of channels and transporters, including those at key endocellular stores, e.g. endoplasmic reticulum (ER), lysosomes, and mitochondria. Along with the highly homologous genes Inositol 1,4,5-trisphosphate (IP3) receptor type 1 (ITPR1) and 2 (ITPR2), ITPR3 encodes the IP3 receptor (IP3R), a key player in intracellular calcium release in animals. Here we report the first cases of ITPR3 defects in man leading to a primarily dysimmune phenotype. In four unrelated patients of diverse ethnicity, and suffering from a complex immunodeficiency syndrome, we report the same de novo pathogenic variant - c.7570C>T; p.Arg2524Cys - in ITPR3. Clinically, recurrent severe infectious episodes of viral and bacterial origins, features of ectodermal dysplasia and that of Charcot-Marie-Tooth disease were paramount. The identified variant does not affect gene transcription, yet it was structurally predicted and biologically proven to disrupt proper protein folding and function in vivo. This eventually leads to defective Calcium flux in patient cells, dysregulation of mitochondrial function and a broad dysimmune phenotype characterized primarily by a profound CD4 T cell lymphopenia associated with quasi absence of naïve CD4 and CD8 cells, itself mirrored by an increase in cognate memory cells. The Calcium signaling defect was recapitulated ex vivo through the introduction of this single variant in Jurkat cells. Moreover, site-directed mutagenesis displayed the exquisite sensitivity of Arg2524 to any amino acid change. In conclusion, a single unique recurrent de novo variant in ITPR3 leads to a novel syndromic immunodeficiency.
Project description:We reported previously that chronic treatment with the Cyclooxygenase-2 inhibitor, rofecoxib, increased acute mortality in rats exposed to ischemia/reperfusion injury (I/R). This manifestation of hidden cardiotoxicity was attributed to the proarrhythmic effect of the drug on the ischemic heart. However, rofecoxib also had beneficial effects on ischemic injury, manifesting as decreased infarct size. In the present study, we aimed to identify molecular changes caused by chronic rofecoxib treatment in the heart. Rats were treated with 5.12 mg/kg rofecoxib or its vehicle for four weeks. Messenger RNA (mRNA), microRNA (miRNA) deep sequencing data, and proteomic datasets of left ventricular tissue samples were used for an unbiased differential expression analysis followed by in silico molecular network analysis and experimental target validation. Using mass spectrometry and filtering criteria, 26 proteins were identified that exhibited pronounced changes in protein expression or phosphorylation due to chronic rofecoxib treatment. The transcriptomic analysis showed mild alterations in the heart´s mRNA- and miRNA expression. The posttranscriptional regulation of mRNAs by miRNAs did not result in differential protein expression. This is the first demonstration that chronic rofecoxib treatment affects posttranslational modification and expression of several proteins in the heart. These are potential off-target effects that could account for the hidden cardiotoxic and/or cardioprotective effects of rofecoxib.
Project description:A 45h time-course RNA-seq study was performed to analyse the different circadian phenotypes of human colorectal cancer cell line HCT116 WT, HCT116 ARNTL Knockout, HCT116 PER2 Knockout and HCT116 NR1D1 Knockout cells. Samples were taken every 3h starting from 9h after cell synchronization for a period of 45h resulting in 16 time-points for each cell line.
Project description:We reported previously that chronic treatment with the Cyclooxygenase-2 inhibitor, rofecoxib, increased acute mortality in rats exposed to ischemia/reperfusion injury (I/R). This manifestation of hidden cardiotoxicity was attributed to the proarrhythmic effect of the drug on the ischemic heart. However, rofecoxib also had beneficial effects on ischemic injury, manifesting as decreased infarct size. In the present study, we aimed to identify molecular changes caused by chronic rofecoxib treatment in the heart. Rats were treated with 5.12 mg/kg rofecoxib or its vehicle for four weeks. Messenger RNA (mRNA), microRNA (miRNA) deep sequencing data, and proteomic datasets of left ventricular tissue samples were used for an unbiased differential expression analysis followed by in silico molecular network analysis and experimental target validation. Using mass spectrometry and filtering criteria, 26 proteins were identified that exhibited pronounced changes in protein expression or phosphorylation due to chronic rofecoxib treatment. The transcriptomic analysis showed mild alterations in the heart´s mRNA- and miRNA expression. The posttranscriptional regulation of mRNAs by miRNAs did not result in differential protein expression. This is the first demonstration that chronic rofecoxib treatment affects posttranslational modification and expression of several proteins in the heart. These are potential off-target effects that could account for the hidden cardiotoxic and/or cardioprotective effects of rofecoxib.
Project description:In cyanobacteria and red algae, the structural basis dictating efficient excitation energy transfer from the phycobilisome (PBS) antenna complex to the reaction centers (RCs) remains unclear. PBS has several peripheral rods and a central core, which binds to the thylakoid membrane, allowing energy coupling with Photosystems II (PSII) and Photosystem I (PSI). Here, we integrated chemical cross-linking mass spectrometry with homology modeling analysis to propose a tri-cylindrical cyanobacterial PBS-core structure. Our model reveals a side view crossover configuration of the two basal cylinders, consolidating the essential roles of the anchoring domains comprised of the ApcE PB-loop and ApcD, which facilitate the energy transfer to PSII and PSI respectively. The uneven bottom surface of the PBS-core contrasts with the flat reducing side of PSII. The extra space between two basal cylinders of the PBS-core and PSII provides increased accessibility of regulatory elements, e.g., orange carotenoid protein, which are required for modulating photochemical activities.
Project description:As part of cross-platform comparisons of microarray and RNA-seq, this current experiment using the Affymetrix Human Transcriptome Array 2.0 aimed to quantify gene-level expression in subjects administered recombinant human erythropoietin over a 10-week protocol for the identification of gene signatures of blood doping. These results were compared to results obtained from other gene expression quantification platforms using the same experimental cohort, including the Illumina HumanHT-12v4 Expression BeadChips (archived in ArrayExpression; E-MTAB-2874), Illumina NextSeq 500 and MGI DNBSEQ-G400RS.
Project description:The host response of the primary intestinal epithelium to human astrovirus (HAstV infection has not been elucidated to date. In order to characterize the global effects of AstV infection on human intestinal tissue, we performed transcriptional profiling of VA1-infected human intestinal enteroids (HIE) by RNAseq. We used the D124 line for our studies since AstV infections are typically symptomatic in very young children, and our prior infection studies indicated rapid infection in D124. D124 HIE were mock-infected or infected with VA1 (MOI = 1) and harvested at 0 hpi (i.e., 1h post-adsorption), 12 hpi, and 24 hpi (Fig 4A). To monitor viral replication, VA1 genome copies were detected by RT-qPCR, revealing an approximately 1 and 2 log increase at 12 and 24 hpi, respectively (Fig 4B). Cellular RNA was extracted and analyzed by RNAseq. Genome copies as determined by RT-qPCR were correlated to the proportion of viral transcripts in the pool of sequenced RNA collected from the same HIE cultures, revealing an exceptionally strong correlation between the two measures of viral replication (r2 = 0.98, P = 2.5 x 10^-14. VA1 genome reads contributed 0.05 ± 0.02 x% of total RNAseq reads at 24 hpi, further confirming robust infection. Differential expression analysis was performed to identify genes associated with the HIE host response to VA1 infection. A total of 23,220 genes were detected. Differential expression of genes at each timepoint was graphed in a volcano plot. The log2 fold change in normalized expression (transcripts per million reads [TPM]) of all expressed host genes in VA1-infected HIEs relative to mock-infected HIE is shown on the x-axis. The -log10 transformed P-value is given on the y-axis. Genes that are significantly up-regulated (adjusted P < 0.05) in VA1-infected D124 HIE relative to mock-infected HIE are colored red, while significantly down-regulated genes are colored blue. Overall, after a 1 hour adsorption (0 hpi), 110 genes were significantly upregulated and 136 genes were downregulated , indicating changes due to viral attachment to cells. This number was reduced at 12 hpi, with 8 significantly upregulated and 5 downregulated genes. At 24 hpi, 154 upregulated and 49 downregulated genes compared to the mock-infected control were identified. We next identified the top 15 significantly up- and down-regulated genes at 24 hpi. This group of genes was used to generated a heatmap of the mean scaled fold-change (Z-score) in expression of each of them in virus-infected HIE relative to mock-infected HIE at each timepoint (Fig 4D). Most of the upregulated genes at 24 hpi were involved in type I and type III interferon (IFN) signaling. Of the IFN genes, IFNL1 was highly upregulated, with IFNA1 and IFNB1 upregulation being slightly lower (Fig S4B). No upregulation was observed for the genes encoding IFN-γ, or the type I and III IFN receptors (data not shown). The top 12 IFN-stimulated genes (ISGs) also positively correlated with VA1 infection (Fig S4C). Conversely, the top 12 downregulated genes, including fermitin family member 1 (FERMT1), signal peptide peptidase like 3 (SPPL3), and tetratricopeptide repeat domain 19 (TTC19) negatively correlated with VA1 infection (Fig S4D). Next, we evaluated lists of the top 100 up- and down-regulated genes at 24 hpi using an over-abundance test to identify significantly over-represented REACTOME pathways in these lists. These data revealed that the top four significantly enriched pathways among upregulated genes were all related to innate antiviral signaling (Fig 4E), which will be investigated in more detail below. For downregulated genes, the top two pathways were “neurexins and neuroligins”, which play signaling roles in synapse development, and “protein-protein interactions at synapses”. The biological significance of synapses during astrovirus infection remains to be elucidated. In order to evaluate the potential for coordinated and directional activation of genes in known signaling pathways, we applied gene set enrichment analysis (GSEA) to our RNAseq differential expression data. Based on the strong dominance of IFN signaling pathways, we focused our GSEA analysis on immune signaling (Fig 4F). During the adsorption phase, nucleic acid pattern recognition receptor signaling pathways (TLRs, STING) were upregulated, consistent with their early role in virus recognition and induction of IFN signaling. At 24 hpi, these early signaling events had been largely replaced by the later phase of IFN signaling and expression of ISGs. Taken together, these data indicate that VA1 infection predominantly elicited antiviral IFN signaling in HIE-derived fetal duodenum at the transcript level.
Project description:DNA methylation is a chemical modification of DNA that can be faithfully inherited across generations in flowering plant genomes. Failure to properly maintain DNA methylation can lead to epigenetic variation and transposon reactivation. Plant genomes are dynamic, spanning large ranges in size and there is an interplay between the genome and epigenome in shaping one another. To understand the variation in genomic patterning of DNA methylation between species, we compared methylomes of numerous diverse angiosperm species. By examining these variations in a phylogenetic context it becomes clear that there is extensive variation in mechanisms that govern gene body DNA methylation, euchromatic silencing of transposons and repeats, as well as silencing of heterochromatic transposons. Extensive variation is observed at all cytosine sequence contexts (CG, CHG and CHH, where H = A, C, T), with the Brassicaceae showing reduced CHG methylation levels and also reduced or loss of CG gene-body methylation. The Poaceae are characterized by a lack or reduction of heterochromatic CHH methylation and enrichment of CHH methylation in genic regions. Reduced CHH methylation levels are found in clonally propagated species, suggesting that these methods of propagation may alter the epigenomic landscape over time, in the absence of sexual reproduction. These results show that DNA methylation targeting pathways have diverged functionally and that extant DNA methylation patterns are likely a reflection of the evolutionary and life histories of plant species. Bisulfite-seq of leaf tissue from plants representing diverse angiosperms. RNA-seq and small RNA-seq was performed on leaf tissue of a subset of the species.