title: Streptomyces-derived quorum-sensing systems engineered for adjustable transgene expression in mammalian cells and mice.
abstract: Prokaryotic transcriptional regulatory elements have been adopted for controlled expression of cloned genes in mammalian cells and animals, the cornerstone for gene-function correlations, drug discovery, biopharmaceutical manufacturing as well as advanced gene therapy and tissue engineering. Many prokaryotes have evolved specific molecular communication systems known as quorum-sensing to coordinate population-wide responses to physiological and/or physicochemical signals. A generic bacterial quorum-sensing system is based on a diffusible signal molecule that prevents binding of a repressor to corresponding operator sites thus resulting in derepression of a target regulon. In Streptomyces, a family of butyrolactones and their corresponding receptor proteins, serve as quorum-sensing systems that control morphological development and antibiotic biosynthesis. Fusion of the Streptomyces coelicolor quorum-sensing receptor (ScbR) to a eukaryotic transactivation domain (VP16) created a mammalian transactivator (SCA) which binds and adjusts transcription from chimeric promoters containing an SCA-specific operator module (P(SPA)). Expression of erythropoietin or the human secreted alkaline phosphatase (SEAP) by this quorum-sensor-regulated gene expression system (QuoRex) could be fine-tuned by non-toxic butyrolactones in a variety of mammalian cells including human primary and mouse embryonic stem cells. Following intraperitoneal implantation of microencapsulated Chinese hamster ovary cells transgenic for QuoRex-controlled SEAP expression into mice, the serum levels of this model glycoprotein could be adjusted to desired concentrations using different butyrolactone dosing regimes.
authors.affiliation: Institute of Biotechnology, Swiss Federal Institute of Technology, ETH Hoenggerberg, CH-8093 Zurich, Switzerland.
authors.forename: Wilfried
authors.initials: W
authors.lastname: Weber
authors.forename: Ronald
authors.initials: R
authors.lastname: Schoenmakers
authors.forename: Manuela
authors.initials: M
authors.lastname: Spielmann
authors.forename: Marie Daoud
authors.initials: MD
authors.lastname: El-Baba
authors.forename: Marc
authors.initials: M
authors.lastname: Folcher
authors.forename: Bettina
authors.initials: B
authors.lastname: Keller
authors.forename: Cornelia C
authors.initials: CC
authors.lastname: Weber
authors.forename: Nils
authors.initials: N
authors.lastname: Link
authors.forename: Petra
authors.initials: P
authors.lastname: van de Wetering
authors.forename: Christoph
authors.initials: C
authors.lastname: Heinzen
authors.forename: Benoît
authors.initials: B
authors.lastname: Jolivet
authors.forename: Urs
authors.initials: U
authors.lastname: Séquin
authors.forename: Dominique
authors.initials: D
authors.lastname: Aubel
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Thompson
authors.forename: Martin
authors.initials: M
authors.lastname: Fussenegger
mesh_terms: D015107:4-Butyrolactone / Q000096:biosynthesis* / Q000494:pharmacology; D000818:Animals; D001426:Bacterial Proteins; D001667:Binding, Competitive; D016466:CHO Cells; D002460:Cell Line; D006224:Cricetinae; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D005818:Genetic Engineering / Q000379:methods*; D006801:Humans; D051379:Mice; D008822:Mice, Transgenic; D010957:Plasmids / Q000235:genetics; D013302:Streptomyces / Q000235:genetics* / Q000378:metabolism; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C446304:ScbR protein, Streptomyces coelicolor; D015107:4-Butyrolactone