Pdx1 and USF transcription factors co-ordinately regulate Alx3 gene expression in pancreatic β-cells

2014 ◽  
Vol 463 (2) ◽  
pp. 287-296 ◽  
Author(s):  
Antonio Fernández-Pérez ◽  
Mario Vallejo
Keyword(s):  
Gene Expression ◽  
Transcription Factors ◽  
Pancreatic Islets ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Transcriptional Transactivation

We investigated the transcriptional mechanisms regulating the expression of Alx3 in pancreatic islets. We found that the transcriptional transactivation of Alx3 in β-cells requires the co-operation of the islet-specific homeoprotein Pdx1 with the transcription factors USF1 and USF2.

scholarly journals Transgene-associated human growth hormone expression in pancreatic β-cells impairs identification of sex-based gene expression differences

2019 ◽  
Vol 316 (2) ◽  
pp. E196-E209 ◽  
Author(s):  
Jennifer S. Stancill ◽  
Anna B. Osipovich ◽  
Jean-Philippe Cartailler ◽  
Mark A. Magnuson
Keyword(s):  
Gene Expression ◽  
Cell Cycle ◽  
Growth Hormone ◽  
Transcription Factors ◽  
Differentially Expressed Genes ◽  
Human Growth ◽  
Differentially Expressed ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Male And Female

Fluorescent protein reporter genes are widely used to identify and sort murine pancreatic β-cells. In this study, we compared use of the MIP-GFP transgene, which exhibits aberrant expression of human growth hormone (hGH), with a newly derived Ins2Apple allele that lacks hGH expression on the expression of sex-specific genes. β-Cells from MIP-GFP transgenic mice exhibit changes in the expression of 7,733 genes, or greater than half of their transcriptome, compared with β-cells from Ins2Apple/+ mice. To determine how these differences might affect a typical differential gene expression study, we analyzed the effect of sex on gene expression using both reporter lines. Six hundred fifty-seven differentially expressed genes were identified between male and female β-cells containing the Ins2Apple allele. Female β-cells exhibit higher expression of Xist, Tmed9, Arpc3, Eml2, and several islet-enriched transcription factors, including Nkx2-2 and Hnf4a, whereas male β-cells exhibited a generally higher expression of genes involved in cell cycle regulation. In marked contrast, the same male vs. female comparison of β-cells containing the MIP-GFP transgene revealed only 115 differentially expressed genes, and comparison of the 2 lists of differentially expressed genes revealed only 17 that were common to both analyses. These results indicate that 1) male and female β-cells differ in their expression of key transcription factors and cell cycle regulators and 2) the MIP-GFP transgene may attenuate sex-specific differences that distinguish male and female β-cells, thereby impairing the identification of sex-specific variations.

Several transcription factors regulate COX-2 gene expression in pancreatic β-cells

2007 ◽  
Vol 34 (3) ◽  
pp. 199-206 ◽  
Author(s):  
Xiongfei Zhang ◽  
Jingjing Zhang ◽  
Xiaomin Yang ◽  
Xiao Han
Keyword(s):  
Gene Expression ◽  
Transcription Factors ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Cox 2

PPARγ is not required for the inhibitory actions of PGJ2 on cytokine signaling in pancreatic β-cells

2004 ◽  
Vol 286 (3) ◽  
pp. E329-E336 ◽  
Author(s):  
Sarah M. Weber ◽  
Anna L. Scarim ◽  
John A. Corbett
Keyword(s):  
Gene Expression ◽  
Nitric Oxide ◽  
Cytokine Signaling ◽  
Rinm5f Cells ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Inos Gene ◽  
Ifn Γ ◽  
Anti Inflammatory ◽  
Inos Gene Expression

Peroxisome proliferator-activated receptor (PPAR)γ agonists, such as 15-deoxy-Δ12,14-prostaglandin J2 (PGJ2) and troglitazone, have been shown to elicit anti-inflammatory effects in pancreatic β-cells that include inhibition of cytokine-stimulated inducible nitric oxide synthase (iNOS) gene expression and production of nitric oxide. In addition, these ligands impair IL-1-induced NF-κB and MAPK as well as IFN-γ-stimulated signal transducer and activator of transcription (STAT)1 activation in β-cells. The purpose of this study was to determine if PPARγ activation participates in the anti-inflammatory actions of PGJ2 in β-cells. Pretreatment of RINm5F cells for 6 h with PGJ2 results in inhibition of IL-1-stimulated IκB degradation and IFN-γ-stimulated STAT1 phosphorylation. Overexpression of a dominant-negative (dn) PPARγ mutant or treatment with the PPARγ antagonist GW-9662 does not modulate the inhibitory actions of PGJ2 on cytokine signaling in RINm5F cells. Although these agents fail to attenuate the inhibitory actions of PGJ2 on cytokine signaling, they do inhibit PGJ2-stimulated PPARγ response element reporter activity. Consistent with the inability to attenuate the inhibitory actions of PGJ2 on cytokine signaling, neither dnPPARγ nor GW-9662 prevents the inhibitory actions of PGJ2 on IL-1-stimulated iNOS gene expression or nitric oxide production by RINm5F cells. These findings support a PPARγ-independent mechanism by which PPARγ ligands impair cytokine signaling and iNOS expression by islets.

scholarly journals Comparison of enteroendocrine cells and pancreatic β-cells using gene expression profiling and insulin gene methylation

PLoS ONE ◽  
2018 ◽  
Vol 13 (10) ◽  
pp. e0206401 ◽  
Author(s):  
Gyeong Ryul Ryu ◽  
Esder Lee ◽  
Jong Jin Kim ◽  
Sung-Dae Moon ◽  
Seung-Hyun Ko ◽  
...  
Keyword(s):  
Gene Expression ◽  
Gene Expression Profiling ◽  
Expression Profiling ◽  
Enteroendocrine Cells ◽  
Insulin Gene ◽  
Gene Methylation ◽  
Β Cells ◽  
Pancreatic Β Cells

scholarly journals The adaptor protein APPL2 controls glucose-stimulated insulin secretion via F-actin remodeling in pancreatic β-cells

2020 ◽  
Vol 117 (45) ◽  
pp. 28307-28315
Author(s):  
Baile Wang ◽  
Huige Lin ◽  
Xiaomu Li ◽  
Wenqi Lu ◽  
Jae Bum Kim ◽  
...  
Keyword(s):  
Insulin Secretion ◽  
Pancreatic Islets ◽  
Adaptor Protein ◽  
Hek293 Cells ◽  
Β Cells ◽  
Β Cell ◽  
Pancreatic Β Cells ◽  
Actin Remodeling ◽  
Actin Depolymerization ◽  
Glucose Stimulated Insulin Secretion

Filamentous actin (F-actin) cytoskeletal remodeling is critical for glucose-stimulated insulin secretion (GSIS) in pancreatic β-cells, and its dysregulation causes type 2 diabetes. The adaptor protein APPL1 promotes first-phase GSIS by up-regulating solubleN-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) protein expression. However, whether APPL2 (a close homology of APPL1 with the same domain organization) plays a role in β-cell functions is unknown. Here, we show that APPL2 enhances GSIS by promoting F-actin remodeling via the small GTPase Rac1 in pancreatic β-cells. β-cell specific abrogation of APPL2 impaired GSIS, leading to glucose intolerance in mice. APPL2 deficiency largely abolished glucose-induced first- and second-phase insulin secretion in pancreatic islets. Real-time live-cell imaging and phalloidin staining revealed that APPL2 deficiency abolished glucose-induced F-actin depolymerization in pancreatic islets. Likewise, knockdown of APPL2 expression impaired glucose-stimulated F-actin depolymerization and subsequent insulin secretion in INS-1E cells, which were attributable to the impairment of Ras-related C3 botulinum toxin substrate 1 (Rac1) activation. Treatment with the F-actin depolymerization chemical compounds or overexpression of gelsolin (a F-actin remodeling protein) rescued APPL2 deficiency-induced defective GSIS. In addition, APPL2 interacted with Rac GTPase activating protein 1 (RacGAP1) in a glucose-dependent manner via the bin/amphiphysin/rvs-pleckstrin homology (BAR-PH) domain of APPL2 in INS-1E cells and HEK293 cells. Concomitant knockdown of RacGAP1 expression reverted APPL2 deficiency-induced defective GSIS, F-actin remodeling, and Rac1 activation in INS-1E cells. Our data indicate that APPL2 interacts with RacGAP1 and suppresses its negative action on Rac1 activity and F-actin depolymerization thereby enhancing GSIS in pancreatic β-cells.

scholarly journals Differentiation of Sendai Virus-Reprogrammed iPSC into β Cells, Compared with Human Pancreatic Islets and Immortalized β Cell Line

2018 ◽  
Vol 27 (10) ◽  
pp. 1548-1560 ◽  
Author(s):  
Silvia Pellegrini ◽  
Fabio Manenti ◽  
Raniero Chimienti ◽  
Rita Nano ◽  
Linda Ottoboni ◽  
...  
Keyword(s):  
Gene Expression ◽  
Pancreatic Islets ◽  
Cell Line ◽  
Expression Profile ◽  
Sendai Virus ◽  
Secretory Function ◽  
Β Cells ◽  
Β Cell ◽  
Insulin Producing Cells ◽  
Gene And Protein Expression

Background: New sources of insulin-secreting cells are strongly in demand for treatment of diabetes. Induced pluripotent stem cells (iPSCs) have the potential to generate insulin-producing cells (iβ). However, the gene expression profile and secretory function of iβ still need to be validated in comparison with native β cells. Methods: Two clones of human iPSCs, reprogrammed from adult fibroblasts through integration-free Sendai virus, were differentiated into iβ and compared with donor pancreatic islets and EndoC-βH1, an immortalized human β cell line. Results: Both clones of iPSCs differentiated into insulin+ cells with high efficiency (up to 20%). iβ were negative for pluripotency markers (Oct4, Sox2, Ssea4) and positive for Pdx1, Nkx6.1, Chromogranin A, PC1/3, insulin, glucagon and somatostatin. iβ basally secreted C-peptide, glucagon and ghrelin and released insulin in response either to increasing concentration of glucose or a depolarizing stimulus. The comparison revealed that iβ are remarkably similar to donor derived islets in terms of gene and protein expression profile and similar level of heterogeneity. The ability of iβ to respond to glucose instead was more related to that of EndoC-βH1. Discussion: We demonstrated that insulin-producing cells generated from iPSCs recapitulate fundamental gene expression profiles and secretory function of native human β cells.

Des-Acyl Ghrelin Fragments and Analogues Promote Survival of Pancreatic β-Cells and Human Pancreatic Islets and Prevent Diabetes in Streptozotocin-Treated Rats

2012 ◽  
Vol 55 (6) ◽  
pp. 2585-2596 ◽  
Author(s):  
Riccarda Granata ◽  
Fabio Settanni ◽  
Michel Julien ◽  
Rita Nano ◽  
Gabriele Togliatto ◽  
...  
Keyword(s):  
Pancreatic Islets ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Human Pancreatic Islets ◽  
Acyl Ghrelin

Tetracaine stimulates insulin secretion through the mobilization of Ca2+ from thapsigargin- and IP3-insensitive Ca2+ reservoir in pancreatic β-cells

2000 ◽  
Vol 78 (6) ◽  
pp. 462-468 ◽  
Author(s):  
José Roberto Bosqueiro ◽  
Everardo Magalhães Carneiro ◽  
Silvana Bordin ◽  
Antonio Carlos Boschero
Keyword(s):  
Insulin Secretion ◽  
Pancreatic Islets ◽  
Isolated Islets ◽  
Inositol Triphosphate ◽  
Free Medium ◽  
Β Cells ◽  
Pancreatic Β Cells ◽  
Isolated Pancreatic Islets ◽  
High Concentrations

The effect of tetracaine on 45Ca efflux, cytoplasmic Ca2+ concentration [Ca2+]i, and insulin secretion in isolated pancreatic islets and β-cells was studied. In the absence of external Ca2+, tetracaine (0.1-2.0 mM) increased the 45Ca efflux from isolated islets in a dose-dependant manner. Tetracaine did not affect the increase in 45Ca efflux caused by 50 mM K+ or by the association of carbachol (0.2 mM) and 50 mM K+. Tetracaine permanently increased the [Ca2+]i in isolated β-cells in Ca2+-free medium enriched with 2.8 mM glucose and 25 µM D-600 (methoxiverapamil). This effect was also observed in the presence of 10 mM caffeine or 1 µM thapsigargin. In the presence of 16.7 mM glucose, tetracaine transiently increased the insulin secretion from islets perfused in the absence and presence of external Ca2+. These data indicate that tetracaine mobilises Ca2+ from a thapsigargin-insensitive store and stimulates insulin secretion in the absence of extracellular Ca2+. The increase in 45Ca efflux caused by high concentrations of K+ and by carbachol indicates that tetracaine did not interfere with a cation or inositol triphosphate sensitive Ca2+ pool in β-cells.

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