title: The PDZ3 domain of the cellular scaffolding protein MAGI-1 interacts with the Coxsackievirus and adenovirus receptor (CAR).
abstract: The Coxsackievirus and adenovirus receptor (CAR) is an essential cellular protein that is involved in cell-cell adhesion, protein trafficking, and viral infection. The major isoform of CAR is selectively sorted to the basolateral membrane of polarized epithelial cells where it co-localizes with the cellular scaffolding protein membrane-associated guanylate kinase with inverted domain structure-1 (MAGI-1). Previously, we demonstrated CAR interacts with MAGI-1 through a PDZ-domain dependent interaction. Here, we show that the PDZ3 domain of MAGI-1 is exclusively responsible for the high affinity interaction between the seven exon isoform of CAR and MAGI-1 using yeast-two-hybrid analysis and confirming this interaction biochemically and in cellular lysates by in vitro pull down assay and co-immunoprecipitation. The high affinity interaction between the PDZ3 domain and CAR C-terminus was measured by fluorescence resonance energy transfer. Further, we investigated the biological relevance of this high affinity interaction between CAR and the PDZ3 domain of MAGI-1 and found that it does not alter CAR-mediated adenovirus infection. By contrast, interruption of this high affinity interaction altered the localization of MAGI-1 indicating that CAR is able to traffic MAGI-1 to cell junctions. These data deepen the molecular understanding of the interaction between CAR and MAGI-1 and indicate that although CAR plays a role in trafficking PDZ-based scaffolding proteins to cellular junctions, association with a high affinity intracellular binding partner does not significantly alter adenovirus binding and entry via CAR.
authors.affiliation: Department of Biological Sciences, Wright State University, Dayton, OH 45435, USA.
authors.forename: Ran
authors.initials: R
authors.lastname: Yan
authors.affiliation: Department of Biological Sciences, Wright State University, Dayton, OH 45435, USA.
authors.forename: Priyanka
authors.initials: P
authors.lastname: Sharma
authors.affiliation: Department of Biological Sciences, Wright State University, Dayton, OH 45435, USA.
authors.forename: Abimbola O
authors.initials: AO
authors.lastname: Kolawole
authors.affiliation: Department of Biological Sciences, Wright State University, Dayton, OH 45435, USA.
authors.forename: Sterling C T
authors.initials: SC
authors.lastname: Martin
authors.affiliation: Department of Biological Sciences, Wright State University, Dayton, OH 45435, USA.
authors.forename: James M
authors.initials: JM
authors.lastname: Readler
authors.affiliation: Department of Biological Sciences, Wright State University, Dayton, OH 45435, USA.
authors.forename: Poornima L N
authors.initials: PL
authors.lastname: Kotha
authors.affiliation: Department of Biochemistry and Molecular Biology, Wright State University, Dayton, OH 45435, USA. Electronic address: heather.hostetler@wright.edu.
authors.forename: Heather A
authors.initials: HA
authors.lastname: Hostetler
authors.affiliation: Department of Biological Sciences, Wright State University, Dayton, OH 45435, USA. Electronic address: katherine.excoffon@wright.edu.
authors.forename: Katherine J D A
authors.initials: KJ
authors.lastname: Excoffon
mesh_terms: D000818:Animals; D016466:CHO Cells; D019556:COS Cells; D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D002522:Chlorocebus aethiops; D062727:Coxsackie and Adenovirus Receptor-Like Membrane Protein / Q000235:genetics / Q000378:metabolism*; D003412:Cricetulus; D008958:Models, Molecular; D054731:PDZ Domains; D014162:Transfection
chemical_list: D015816:Cell Adhesion Molecules, Neuronal; D062727:Coxsackie and Adenovirus Receptor-Like Membrane Protein
keywords: Adenovirus; Cell junction; Epithelia; PDZ domain