Project description:Misfolded membrane proteins are retained in the endoplasmic reticulum (ER) and are subject to the ER associated degradation pathway, which clears the secretory pathway of potentially toxic species. While the transcriptional response to environmental stressors has been extensively studied, limited data exist describing the cellular response to misfolded membrane proteins. To this end, we expressed and then compared the transcriptional profiles elicited by the synthesis of three ER retained, misfolded ion channels: The α subunit of the epithelial sodium channel, ENaC, the cystic fibrosis transmembrane conductance regulator, CFTR, and an inwardly rectifying potassium channel, Kir2.1, which vary in their mass, membrane topologies, and quaternary structures. To examine transcriptional profiles in a null background, the proteins were expressed in yeast, which was previously used to examine the degradation requirements for each substrate. Surprisingly, the proteins failed to induce a canonical unfolded protein response or heat shock response, although messages encoding several cytosolic and ER lumenal protein folding factors rose when αENaC or CFTR were expressed. In contrast, the levels of these genes were unaltered by Kir2.1 expression; instead, the yeast iron regulon was activated. Nevertheless, a significant number of genes that respond to various environmental stressors were upregulated by all three substrates, and when compared to previous microarray data we deduced the existence of a group of genes that reflect a novel misfolded membrane protein response. These data indicate that aberrant proteins in the ER elicit profound yet unique cellular responses. Yeast heterologously expressing αENaC, CFTR, Kir2.1 or harboring a vector control were grown under identical conditions (at least 3 biological replicates) and subject to gene expression analysis.
Project description:Misfolded membrane proteins are retained in the endoplasmic reticulum (ER) and are subject to the ER associated degradation pathway, which clears the secretory pathway of potentially toxic species. While the transcriptional response to environmental stressors has been extensively studied, limited data exist describing the cellular response to misfolded membrane proteins. To this end, we expressed and then compared the transcriptional profiles elicited by the synthesis of three ER retained, misfolded ion channels: The α subunit of the epithelial sodium channel, ENaC, the cystic fibrosis transmembrane conductance regulator, CFTR, and an inwardly rectifying potassium channel, Kir2.1, which vary in their mass, membrane topologies, and quaternary structures. To examine transcriptional profiles in a null background, the proteins were expressed in yeast, which was previously used to examine the degradation requirements for each substrate. Surprisingly, the proteins failed to induce a canonical unfolded protein response or heat shock response, although messages encoding several cytosolic and ER lumenal protein folding factors rose when αENaC or CFTR were expressed. In contrast, the levels of these genes were unaltered by Kir2.1 expression; instead, the yeast iron regulon was activated. Nevertheless, a significant number of genes that respond to various environmental stressors were upregulated by all three substrates, and when compared to previous microarray data we deduced the existence of a group of genes that reflect a novel misfolded membrane protein response. These data indicate that aberrant proteins in the ER elicit profound yet unique cellular responses. Yeast heterologously expressing αENaC, CFTR, Kir2.1 or harboring a vector control were grown under identical conditions (at least 3 biological replicates) and subject to gene expression analysis.
Project description:Misfolded membrane proteins are retained in the endoplasmic reticulum (ER) and are subject to the ER associated degradation pathway, which clears the secretory pathway of potentially toxic species. While the transcriptional response to environmental stressors has been extensively studied, limited data exist describing the cellular response to misfolded membrane proteins. To this end, we expressed and then compared the transcriptional profiles elicited by the synthesis of three ER retained, misfolded ion channels: The α subunit of the epithelial sodium channel, ENaC, the cystic fibrosis transmembrane conductance regulator, CFTR, and an inwardly rectifying potassium channel, Kir2.1, which vary in their mass, membrane topologies, and quaternary structures. To examine transcriptional profiles in a null background, the proteins were expressed in yeast, which was previously used to examine the degradation requirements for each substrate. Surprisingly, the proteins failed to induce a canonical unfolded protein response or heat shock response, although messages encoding several cytosolic and ER lumenal protein folding factors rose when αENaC or CFTR were expressed. In contrast, the levels of these genes were unaltered by Kir2.1 expression; instead, the yeast iron regulon was activated. Nevertheless, a significant number of genes that respond to various environmental stressors were upregulated by all three substrates, and when compared to previous microarray data we deduced the existence of a group of genes that reflect a novel misfolded membrane protein response. These data indicate that aberrant proteins in the ER elicit profound yet unique cellular responses. Yeast heterologously expressing αENaC, CFTR, Kir2.1 or harboring a vector control were grown under identical conditions (at least 3 biological replicates) and subject to gene expression analysis.
Project description:Background Urothelial carcinoma of the bladder (UC) is a common malignancy. Although extensive transcriptome analysis has provided insights into the gene expression patterns of this tumor type, the mechanistic underpinnings of differential methylation remain poorly understood. Multi-level genomic data may be used to profile the regulatory potential and landscape of differential methylation in cancer and gain understanding of the processes underlying epigenetic and phenotypic characteristics of tumors. Methods We perform genome-wide DNA methylation profiling of 98 gene-expression subtyped tumors to identify between-tumor differentially methylated regions (DMRs). We integrate multi-level publically available genomic data generated by the ENCODE consortium to characterize the regulatory potential of UC DMRs. Results We identify 5,453 between-tumor DMRs and derive four DNA methylation subgroups of UC with distinct associations to clinicopathological features and gene expression subtypes. We characterize three distinct patterns of differential methylation and use ENCODE data to show that tumor subgroup-defining DMRs display differential chromatin state, and regulatory factor binding preferences. Finally, we characterize an epigenetic switch involving the HOXA-genes with associations to tumor differentiation states and patient prognosis. Conclusions Genome-wide DMR methylation patterns are reflected in the gene expression subtypes of UC. UC DMRs display three distinct methylation patterns, each associated with intrinsic features of the genome and differential regulatory factor binding preferences. Epigenetic inactivation of HOX-genes correlates with tumor differentiation states and may present an actionable epigenetic alteration in UC. MeDIP hybridizations on 98 human urothelial carcinoma samples and 4 normal urothelium samples on Nimblegen 3x720K RefSeq Promoter and CGI aCGH arrays.
Project description:We report quantitation of specific mRNAs in two RNA samples isolated from normozoospermic whole semen Examination of 2 different normozoospermic semen samples by RNA-seq Please note that raw data for 'GSM1273824: AY4' is incomplete.
Project description:A total of 58 genes were up-regulated (> 1.5 fold-change) while 117 genes were down-regulated Microarray experiments were performed in duplicate as follows: MDA-MB-468 cells were transduced with lentiviral shRNA targeting endogenous p53-R273H mutant (p53si-1)or a non-targeting shRNA (NS). Total RNA from cells was extracted using Qiagen RNA isolation kit (Qiagen, Valencia, CA, USA) according to the manufacturersâ protocol. RNA purity was examined by spectrophotometric determination at 260/280 nm. The microarray hybridizations were carried out using the Affymetrix Human Gene 1.0 ST arrays.
Project description:Neural stem cells (NSCs) are considered to be the cell-of-origin of brain tumor stem cells. To identify the genetic pathways responsible for the transformation of normal NSCs to brain-tumor-initiating cells, we used Sleeping Beauty (SB) transposons, to mutagenize NSCs. Mobilized SB transposons induced the immortalization of NSCs. Immortalized NSCs induced tumors upon subcutaneous transplantation in immunocompromized mice. To further classify the immortalized cells and mouse tumors, we performed Gene Set Enrichment Analysis (GSEA) using DNA microarray data. Ten immortalized NSC lines (four WT and six p53 mutant lines) and two normal NSCs were used for RNA extraction and hybridization on Affymetrix microarrays. CEL files were processed using the RMA algorithm to normalize the data. Unsupervised hierarchical clustering was applied to the normalized gene expression data across samples using the R module pvclust (Suzuki and Shimodaira, Bioinformatics 22, 1540-1542, 2006). Hierarchical clustering showed a close similarity in gene expression between all ten immortalized lines, compared with two normal NSCs. We then compared their gene expression profiles to those present in the brain transcriptome database (Cahoy et al., J Neurosci 28, 264-278, 2008). Using five gene sets that are associated with neurons, oligodendrocytes, OPCs, astrocytes and cultured astroglial cells, GSEA enrichment scores were calculated for the ten immortalized NSCs lines against two control normal NSCs. GSEA enrichment analysis was performed using GSEA software v. 2.07 (http://www.broadinstitute.org/gsea). We found a strong enrichment for genes that are differentially expressed in the cultured astroglial cells. Twelve tumors (six WT and six p53 mutant tumors) and three control subcutaneous tissues were used for RNA extraction and hybridization on Affymetrix microarrays. CEL files were processed using the RMA algorithm to normalize the data. Unsupervised hierarchical clustering was applied to the normalized gene expression data across samples using the R module pvclust (Suzuki and Shimodaira, Bioinformatics 22, 1540-1542, 2006). Hierarchical clustering of 12 tumors showed a close similarity between the tumors, compared with three control subcutaneous tissues. We next performed GSEA analysis on the tumors. Using gene sets specific to the four defined GBM subtypes (Verhaak et al., Cancer Cell 17, 98-110, 2010), a GSEA enrichment score was then calculated for the twelve tumor samples against three control subcutaneous tissue samples. GSEA enrichment analysis was performed using GSEA software v. 2.07 (http://www.broadinstitute.org/gsea). This analysis showed that the mouse tumors were significantly enriched for genes specific for the mesenchymal GBM. Immortalized cell lines and tumors were used for RNA extraction and hybridization on Affymetrix microarrays. Ten immortalized lines (Line 3, 28, 31, 59, 95, 116, 119, 120, 123, 331) were compared with two normal NSCs. Twelve tumors were generated from four lines (1, 31, 59, 123) and compared with three subcutaneous tissues (SubQ).
Project description:Micro RNAs (miRNAs) are a class of small, non-coding RNA species that play critical roles throughout cellular development and regulation. miRNA expression patterns taken from various tissue types often point to the cellular lineage of an individual tissue Arrays for serum miRNA analysis were constructed with 547 human miRNA sequences obtained from the Sanger Database version 10.0 which appeared on 8/2/07. Because of limited space on the array, the probe list was modified to exclude a few newer miRNAs that had recently been added. The array includes miRNA probes for all studies referenced by this paper. Three probes were written for each miRNA: an anti-sensed wild-type version, a double-mutant control probe, and a sense control version. Antisense controls were not included if the corresponding antisense miRNA existed in the databases. The double mutant control mutations were screened in order to maintain the same notional melting temperature (Tm) as the wild-type Tm. They were also designed to avoid perturbing or creating any secondary structure that might appear in the wild-type probe. In addition to the 547 human miRNAs, we also included as controls, four sheep, three C. elegans, and two human sequences.
Project description:A total of 18 genes were up-regulated and 11 genes were down-regulated > 2-fold following 6-shogaol treatment Microarray experiments were performed in duplicate as follows: MCF-7 cells were treated with 10 uM of 6-shogaol or control vehicle (0.1% DMSO) for 48 h. Total RNA from cells was extracted using Qiagen RNA isolation kit (Qiagen, Valencia, CA, USA) according to the manufacturersM-bM-^@M-^Y protocol. RNA purity was examined by spectrophotometric determination at 260/280 nm. The microarray hybridizations were carried out using the Affymetrix Human Gene 1.0 ST arrays.
Project description:Analysis of wildtype (N2) C. elegans fed different diets: E. coli OP50, Comamonas DA1877, and Diluted Comamonas (1:1000 Comamonas DA1877:E. coli OP50) Dietary composition has major effects on physiology. Here we show that developmental rate, reproduction and lifespan are altered in C. elegans fed Comamonas DA1877 relative to those fed a standard E. coli OP50 diet. We identify a set of genes that change in expression in response to this diet, and use the promoter of one of these (acdh-1) as a dietary sensor. Remarkably, the effects on transcription and development occur even when Comamonas DA1877 is diluted with another diet, suggesting that Comamonas DA1877 generates a signal that is sensed by the nematode. Surprisingly, the developmental effect is independent from TOR and insulin signaling. Rather, Comamonas DA1877 affects cyclic gene expression during molting, likely through the nuclear hormone receptor NHR-23. Altogether, our findings indicate that different bacteria elicit various responses via distinct mechanisms, which has implications for diseases such as obesity and the interactions between the human microbiome and intestinal cells. 3 biological replicates for each condition, OP50 is reference sample