title: Evidence for new homotypic and heterotypic interactions between transmembrane helices of proteins involved in receptor tyrosine kinase and neuropilin signaling.
abstract: Signaling in eukaryotic cells frequently relies on dynamic interactions of single-pass membrane receptors involving their transmembrane (TM) domains. To search for new such interactions, we have developed a bacterial two-hybrid system to screen for both homotypic and heterotypic interactions between TM helices. We have explored the dimerization of TM domains from 16 proteins involved in both receptor tyrosine kinase and neuropilin signaling. This study has revealed several new interactions. We found that the TM domain of Mucin-4, a putative intramembrane ligand for erbB2, dimerizes not only with erbB2 but also with all four members of the erbB family. In the Neuropilin/Plexin family of receptors, we showed that the TM domains of Neuropilins 1 and 2 dimerize with themselves and also with Plexin-A1, Plexin-B1, and L1CAM, but we were unable to observe interactions with several other TM domains notably those of members of the VEGF receptor family. The potentially important Neuropilin 1/Plexin-A1 interaction was confirmed using a surface plasmon resonance assay. This work shows that TM domain interactions can be highly specific. Exploring further the propensities of TM helix-helix association in cell membrane should have important practical implications related to our understanding of the structure-function of bitopic proteins' assembly and subsequent function, especially in the regulation of signal transduction.
authors.affiliation: Laboratoire d'Ingénierie des Systèmes Macromoléculaires, UMR 7255, Centre National de la Recherche Scientifique and Aix-Marseille University, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France.
authors.forename: Paul
authors.initials: P
authors.lastname: Sawma
authors.affiliation: INSERM U 1109 and University of Strasbourg, 3 Avenue Molière, 67200 Strasbourg, France.
authors.forename: Lise
authors.initials: L
authors.lastname: Roth
authors.affiliation: Laboratoire d'Ingénierie des Systèmes Macromoléculaires, UMR 7255, Centre National de la Recherche Scientifique and Aix-Marseille University, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Blanchard
authors.affiliation: INSERM U 1109 and University of Strasbourg, 3 Avenue Molière, 67200 Strasbourg, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Bagnard
authors.affiliation: INSERM U 1109 and University of Strasbourg, 3 Avenue Molière, 67200 Strasbourg, France.
authors.forename: Gérard
authors.initials: G
authors.lastname: Crémel
authors.affiliation: Laboratoire d'Ingénierie des Systèmes Macromoléculaires, UMR 7255, Centre National de la Recherche Scientifique and Aix-Marseille University, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France.
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Bouveret
authors.affiliation: Laboratoire d'Ingénierie des Systèmes Macromoléculaires, UMR 7255, Centre National de la Recherche Scientifique and Aix-Marseille University, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Duneau
authors.affiliation: Laboratoire d'Ingénierie des Systèmes Macromoléculaires, UMR 7255, Centre National de la Recherche Scientifique and Aix-Marseille University, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France.
authors.forename: James N
authors.initials: JN
authors.lastname: Sturgis
authors.affiliation: Laboratoire d'Ingénierie des Systèmes Macromoléculaires, UMR 7255, Centre National de la Recherche Scientifique and Aix-Marseille University, 31 Chemin Joseph Aiguier, 13402 Marseille Cedex 20, France. Electronic address: phubert@imm.cnrs.fr.
authors.forename: Pierre
authors.initials: P
authors.lastname: Hubert
mesh_terms: D000595:Amino Acid Sequence; D015153:Blotting, Western; D002462:Cell Membrane / Q000378:metabolism*; D006801:Humans; D008856:Microscopy, Fluorescence; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D039842:Neural Cell Adhesion Molecule L1 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D039942:Neuropilin-1 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D039943:Neuropilin-2 / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding; D025941:Protein Interaction Mapping / Q000379:methods; D055503:Protein Multimerization; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D020794:Receptor Protein-Tyrosine Kinases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D020798:Two-Hybrid System Techniques
chemical_list: D009419:Nerve Tissue Proteins; D039842:Neural Cell Adhesion Molecule L1; D039943:Neuropilin-2; C492119:PLXNB1 protein, human; D011956:Receptors, Cell Surface; D039942:Neuropilin-1; D020794:Receptor Protein-Tyrosine Kinases
keywords: cell surface receptor; protein–protein interactions; signal transduction; transmembrane domain; two-hybrid assay