title: A ToxR-based dominant-negative system to investigate heterotypic transmembrane domain interactions.
abstract: The ToxR transcription activator system is a genetic tool widely used to examine homotypic interactions of alpha-helical transmembrane domains that drive or support oligomerization of integral membrane proteins. Here, we present a variant of this system that was developed to investigate heterotypic interactions. In this system, a homotypically interacting transmembrane domain within the ToxR protein is coexpressed with a potential competitor that is embedded within an inactivated ToxR mutant. Successful heterotypic interaction competes with homotypic interaction in a dominant-negative fashion as revealed by reduced reporter gene transcription. We expect that this system will be useful for the characterization of transmembrane domains whose homotypic and heterotypic interactions compete with each other.
authors.affiliation: Technische Universität München, Lehrstuhl für Chemie der Biopolymere, Weihenstephaner Berg 3,D-85354 Freising-Weihenstephan, Germany.
authors.forename: Eric
authors.initials: E
authors.lastname: Lindner
authors.forename: Dieter
authors.initials: D
authors.lastname: Langosch
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D002462:Cell Membrane; D004268:DNA-Binding Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D017930:Genes, Reporter; D008565:Membrane Proteins / Q000737:chemistry*; D008954:Models, Biological; D008969:Molecular Sequence Data; D009154:Mutation; D017510:Protein Folding; D017434:Protein Structure, Tertiary; D016415:Sequence Alignment; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D008565:Membrane Proteins; D014157:Transcription Factors; C499324:toxR protein, Vibrio cholerae