Project description:Increasing evidence suggests that loss of beta cell characteristics may cause insulin secretory deficiency in diabetes but the underlying mechanisms remain unclear. Here we show that Rfx6, whose mutation leads to neonatal diabetes in man, is essential to maintain key features of functionally mature beta cells in mice. Rfx6 loss in adult beta cells leads to glucose intolerance, impaired beta cell glucose sensing and to defective insulin secretion. This is associated with reduced expression of core components of the insulin secretion pathway including GLucokinase, the Abcc8/SUR1 subunit of KATP channels and voltage-gated Ca2 channels, which are direct targets of Rfx6. Moreover, Rfx6 contributes to the silencing of the vast majority of M-bM-^@M-^\disallowedM-bM-^@M-^] genes, a group usually specifically repressed in adult beta cells, and thus to the maintenance of beta cell maturity. These findings raise the possibility that changes in Rfx6 expression or activity may contribute to beta cell failure in man. Two ChIP-Seq experiments have been performed : 1) anti-HA ChIP-Seq on 3HA-Rfx6 transfected Min6b1 cells and 2) anti-HA ChIP-Seq on Min6b1 cells
Project description:We have shown that β-catenin overexpression induced blockage of monocyte-macrophage differentiation by inhibiting PU.1-targeted gene transcription including Egr2 expression in myeloid progenitor cells. Our results suggest that compromised PU.1-targeted gene transcription induced by β-catenin overexpression, at least partially, may mediate a pathogenic role of β-catenin in myeloid leukemia.
Project description:To identify genes regulated by Oxi-beta, differential gene chip analysis was perfomed. And the greatest upregulation (about 25-fold) of FBXW5 mRNA was observed in response to Oxi-beta overexpression in SN4741 dopaminergic neuronal cells Total RNAs obtained from subjected to overexpression of Oxi-beta for 12 hours compared to control SN4741 cells at 0 hr.
Project description:The goal of this study is to compare the transcriptome of mouse beta-cells expressing mutant constitutively active Glucokinase versus wild-type Glucokinase.
Project description:Increasing evidence suggests that loss of beta cell characteristics may cause insulin secretory deficiency in diabetes but the underlying mechanisms remain unclear. Here we show that Rfx6, whose mutation leads to neonatal diabetes in man, is essential to maintain key features of functionally mature beta cells in mice. Rfx6 loss in adult beta cells leads to glucose intolerance, impaired beta cell glucose sensing and to defective insulin secretion. This is associated with reduced expression of core components of the insulin secretion pathway including GLucokinase, the Abcc8/SUR1 subunit of KATP channels and voltage-gated Ca2 channels, which are direct targets of Rfx6. Moreover, Rfx6 contributes to the silencing of the vast majority of “disallowed” genes, a group usually specifically repressed in adult beta cells, and thus to the maintenance of beta cell maturity. These findings raise the possibility that changes in Rfx6 expression or activity may contribute to beta cell failure in man.
Project description:Total RNA were extracted from Guanylate Cyclase Soluble Subunit Beta-3 (GUCY1B3) overexpression U87 MG stable cell lines and U87 MG cells. Three RNA samples of each of the two cell lines were used for microarray analysis to compare gene expression profile Guanylate Cyclase Soluble Subunit Beta-3 (GUCY1B3) was cloned into pCDNA3.1D/V5-His-TOPO plasmid (Invitrgen) and then transfected into U87 MG (ATCC HTB-1) cells to generate stable overexpression cells. RNA from the stable cell lines and U87 MG were used for microarray
Project description:Pancreatic beta cells use electrical signals to couple changes in blood glucose concentration to insulin release via extracellular calcium (Ca2+) influx. Sorcin (SRI) is a Ca2+-binding protein whose overexpression in cardiomyocytes rescues the abnormal contractile function of the diabetic heart. In order to investigate the role of sorcin in regulating mouse pancreatic beta cell transcriptome, transgenic mice were generated on a C56BL/6 background permitting inducible overexpression of SRI cDNA with the TetOn-system specifically in beta cells. Animals bearing ten copies of the SRI transgene (SRI-tg10), and littermate controls, were fed a high fat diet (60% fat, HFD) and exposed to doxycycline in the drinking water (500mg/L) from 4 weeks onwards. Microarray analysis were performed using total RNA from isolated pancreatic islets of 8-week-old mice.
Project description:To identify genes regulated by Oxi-beta, differential gene chip analysis was perfomed. And the greatest upregulation (about 25-fold) of FBXW5 mRNA was observed in response to Oxi-beta overexpression in SN4741 dopaminergic neuronal cells