Overexpression of spliced XBP1 in cultured Adipocytes
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE46178 | GEO | 2013/04/19
SECONDARY ACCESSION(S): PRJNA197508
REPOSITORIES: GEO
Similar Datasets
Project description:We overexpressed the spliced form of transcription factor XBP1 in mature F442A adipocytes by adenoviral infection. Control virus expressed GFP alone. mouse sXBP1 overexpressed in mouse F442A adipocytes compared to control (GFP alone). Four replicates of each treatment were analyzed.
2013-04-19 | E-GEOD-46178 | biostudies-arrayexpress
Project description:BACKGROUND AND AIM: We previously established that endoplasmic reticulum stress leads to unfolded protein response (UPR) that promotes liver fibrosis by activating hepatic stellate cell (HSC). We aimed to determine the role of X-box binding protein 1 (XBP1), one of three UPR effector pathways, in the fibrogenic HSC activation. METHODS: XBP1 expression was measured by qPCR in tunicamycin-treated human HSC lines (TWNT4 and LX2) and culture-activated human primary HSCs. XBP1 was overexpressed in primary human HSCs and the HSC lines, and fibrogenic genes (COL1A1, ACTA2, PDGFRB, MMP2, TIMP1) and encoded proteins were assessed by qPCR and Western blotting, respectively. Autophagy was inhibited by knockdown of ATG7. Genome-wide transcriptome profiling was performed to determine modulated molecular pathway by XBP1. In vivo XBP1 activation was assessed in transcriptome datasets of fibrotic mouse models and immunohistochemistry of human liver tissues. RESULTS: XBP1 overexpression accompanied both tunicamycin- and culture-based HSC activation. Ectopic overexpression of XBP1 induced fibrogenic gene expression in the HSC lines, which was inhibited by knockdown of ATG7. UPR pathway together with PDGFRB pathway, a hallmark of HSC activation, were induced in transcriptome profiles of XBP1-transduced HSC lines. Some known fibrogenic pathways such as transforming growth factor (TGF)-beta pathway were not induced, suggesting partial contribution of XBP1 to the entire fibrogenic HSC activation machinery. XBP1 target gene signature defined in our XBP1-overexpressing HSC lines was significantly induced in liver tissue transcriptome profiles of carbon tetrachloride-treated or bile duct-ligated mouse models, and XBP1 and alpha-smooth muscle actin (encoded by ACTA2, another hallmark of HSC activation) were co-localized in human fibrotic liver tissues, collectively supporting involvement of XBP1 in HSC activation and fibrogesis in vivo. CONCLUSIONS: XBP1-mediated UPR is at least partially responsible for fibrogenic HSC activation via autophagy.
2016-12-21 | GSE78070 | GEO
Project description:Transcriptional profiling of INS1 cells expressing either WT IRE1α, I642G IRE1α, N906A IRE1α, or spliced XBP1 comparing 1μg/mL dox and 5μM 1NMPP1 treated vs control.
2014-12-22 | GSE17148 | GEO
Project description:Transcriptional profiling of INS1 cells expressing either WT IRE1α, I642G IRE1α, N906A IRE1α, or spliced XBP1 comparing 1μg/mL dox and 5μM 1NMPP1 treated vs control. All arrays are hybed pairwise with treated hybed against untreated
2014-12-22 | E-GEOD-17148 | biostudies-arrayexpress
Project description:Overexpression of spliced XBP1 in in vitro Th2 cells, and comparison to 4u8c treatment
| PRJEB28078 | ENA
Project description:Overexpression of spliced XBP1 in cultured Adipocytes
| PRJNA197508 | ENA
Project description:Human X-box binding protein-1 (XBP1) is an alternatively spliced transcription factor that participates in the unfolded protein response (UPR), a stress signaling pathway that allows cells to survive the accumulation of unfolded proteins in the endoplasmic reticulum lumen. We have previously demonstrated that XBP1 expression is increased in antiestrogen-resistant breast cancer cell lines, and is co-expressed with estrogen receptor alpha (ER) in breast tumors. The purpose of this study is to investigate the role of XBP1 and the UPR in estrogen and antiestrogen responsiveness in breast cancer. Overexpression of spliced XBP1 (XBP1(S)) in ER-positive breast cancer cells leads to estrogen-independent growth and reduced sensitivity to growth inhibition induced by the antiestrogens Tamoxifen and Faslodex in a manner independent of functional p53. Data from gene expression microarray analyses imply that XBP1(S) acts through regulating the expression of ER, the anti-apoptotic gene BCL2, and several other genes associated with control of the cell cycle and apoptosis. Keywords: genetic modification (effect of gene knock-in, stable transfection)
2007-08-13 | GSE8562 | GEO
Project description:Signaling cascades during adipogenesis culminate in the expression of two essential adipogenic factors, PPARγ and C/EBPα. Here we demonstrate that the IRE1α-XBP1 pathway, the most conserved branch of the unfolded protein response (UPR), is indispensable for adipogenesis. Indeed, XBP1-deficient mouse embryonic fibroblasts and 3T3-L1 cells with XBP1 or IRE1α knockdown exhibit profound defects in adipogenesis. Intriguingly, C/EBPβ, a key early adipogenic factor, induces Xbp1 expression by directly binding to its proximal promoter region. Subsequently, XBP1 binds to the promoter of Cebpa and activates its gene expression. The posttranscriptional splicing of Xbp1 mRNA by IRE1α is required as only the spliced form of XBP1 (XBP1s) rescues the adipogenic defect exhibited by XBP1-deficient cells. Taken together, our data show that the IRE1α-XBP1 pathway plays a key role in adipocyte differentiation by acting as a critical regulator of the morphological and functional transformations during adipogenesis. The Xbp1 deficient MEFs are subjected to adipogenesis using standard drug induction. The cells are collected at day 0 and day 3. Total RNA are extracted from the cells and used for one channel microarray analysis. Expression levels on day 3 are compared to that on day 0.
2010-06-19 | E-GEOD-15771 | biostudies-arrayexpress
Project description:Signaling cascades during adipogenesis culminate in the expression of two essential adipogenic factors, PPARγ and C/EBPα. Here we demonstrate that the IRE1α-XBP1 pathway, the most conserved branch of the unfolded protein response (UPR), is indispensable for adipogenesis. Indeed, XBP1-deficient mouse embryonic fibroblasts and 3T3-L1 cells with XBP1 or IRE1α knockdown exhibit profound defects in adipogenesis. Intriguingly, C/EBPβ, a key early adipogenic factor, induces Xbp1 expression by directly binding to its proximal promoter region. Subsequently, XBP1 binds to the promoter of Cebpa and activates its gene expression. The posttranscriptional splicing of Xbp1 mRNA by IRE1α is required as only the spliced form of XBP1 (XBP1s) rescues the adipogenic defect exhibited by XBP1-deficient cells. Taken together, our data show that the IRE1α-XBP1 pathway plays a key role in adipocyte differentiation by acting as a critical regulator of the morphological and functional transformations during adipogenesis.
2009-04-25 | GSE15771 | GEO
Project description:Human X-box binding protein-1 (XBP1) is an alternatively spliced transcription factor that participates in the unfolded protein response (UPR), a stress signaling pathway that allows cells to survive the accumulation of unfolded proteins in the endoplasmic reticulum lumen. We have previously demonstrated that XBP1 expression is increased in antiestrogen-resistant breast cancer cell lines, and is co-expressed with estrogen receptor alpha (ER) in breast tumors. The purpose of this study is to investigate the role of XBP1 and the UPR in estrogen and antiestrogen responsiveness in breast cancer. Overexpression of spliced XBP1 (XBP1(S)) in ER-positive breast cancer cells leads to estrogen-independent growth and reduced sensitivity to growth inhibition induced by the antiestrogens Tamoxifen and Faslodex in a manner independent of functional p53. Data from gene expression microarray analyses imply that XBP1(S) acts through regulating the expression of ER, the anti-apoptotic gene BCL2, and several other genes associated with control of the cell cycle and apoptosis. Experiment Overall Design: Total RNA was isolated from six independent cultures (cell populations grown on different days from different stocks); three from MCF7/XBP1 cultures and three from the vector control cultures. MIAME 1.1 compliant data were collected as recommended by the Microarray Gene Expression Data (MGED) Society. RNA concentrations were determined by comparing the optical density ratios (260:280 nm) , and data on RNA quality was obtained using an Agilent 2100 Bioanalyzer and RNA 6000 LabChip kits (Agilent Technologies, New Castle, DE). RNA quality was assessed by visual inspection of the electropherograms from the Bioanalyzer data, and by the calculated RNA integrity numbers (RIN) and Degradometer values . Only high quality total RNA was labeled and hybridized to U133A Affymetrix GeneChips using manufacturer recommended procedures (Affymetrix, Santa Clara, CA). Standard âspiked-inâ controls also were included in each hybridization.
2008-06-16 | E-GEOD-8562 | biostudies-arrayexpress