title: Expression, signaling and function of Egr transcription factors in pancreatic β-cells and insulin-responsive tissues.
abstract: Egr-1 and the related zinc finger transcription factors Egr-2, Egr-3, and Egr-4 are stimulated by many extracellular signaling molecules and represent a convergence point for intracellular signaling cascades. Egr-1 expression is induced in insulinoma cells and pancreatic β-cells following stimulation with either glucose, or pregnenolone sulfate. Moreover, stimulation of Gαq and Gαs-coupled receptors enhances EGR-1 gene transcription. Functional studies revealed that Egr transcription factors control insulin biosynthesis via regulation of Pdx-1 expression. Glucose homeostasis and pancreatic islet size are regulated by Egr transcription factors, indicating that these proteins control central physiological parameters regulated by pancreatic β-cells. In addition, Egr-1 is an integral part of the insulin receptor signaling cascade in insulin-responsive tissues and influences insulin resistance.
authors.affiliation: Department of Medical Biochemistry and Molecular Biology, University of Saarland Medical Center, D-66421 Homburg, Germany. Electronic address: gerald.thiel@uks.eu.
authors.forename: Gerald
authors.initials: G
authors.lastname: Thiel
authors.affiliation: Department of Medical Biochemistry and Molecular Biology, University of Saarland Medical Center, D-66421 Homburg, Germany.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Müller
authors.affiliation: Department of Medical Biochemistry and Molecular Biology, University of Saarland Medical Center, D-66421 Homburg, Germany.
authors.forename: Oliver G
authors.initials: OG
authors.lastname: Rössler
mesh_terms: D000818:Animals; D001483:Base Sequence; D051765:Early Growth Response Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015870:Gene Expression; D005786:Gene Expression Regulation; D006801:Humans; D007328:Insulin; D050417:Insulin-Secreting Cells / Q000378:metabolism*; D007340:Insulinoma / Q000378:metabolism; D009928:Organ Specificity; D011401:Promoter Regions, Genetic; D015398:Signal Transduction
chemical_list: D051765:Early Growth Response Transcription Factors; D007328:Insulin
keywords: Beta cell; Egr-1; Insulin; Pancreas; Pdx-1; Transcription