title: Structural features of aquaporin 4 supporting the formation of arrays and junctions in biomembranes.
abstract: A limited class of aquaporins has been described to form regular arrays and junctions in membranes. The biological significance of these structures, however, remains uncertain. Here we analyze the underlying physical principles with the help of a computational procedure that takes into account protein-protein as well as protein-membrane interactions. Experimentally observed array/junction structures are systematically (dis)assembled and major driving forces identified. Aquaporin 4 was found to be markedly different from the non-junction forming aquaporin 1. The environmental stabilization resulting from embedding into the biomembrane was identified as the main driving force. This highlights the role of protein-membrane interactions in aquaporin 4. Analysis of the type presented here can help to decipher the biological role of membrane arrays and junctions formed by aquaporin.
authors.affiliation: Dipartimento di Chimica, Università di Bologna, Bologna, Italy. siegfried.hoefinger@unibo.it
authors.forename: Siegfried
authors.initials: S
authors.lastname: Höfinger
authors.forename: Eiji
authors.initials: E
authors.lastname: Yamamoto
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Hirano
authors.forename: Francesco
authors.initials: F
authors.lastname: Zerbetto
authors.forename: Tetsu
authors.initials: T
authors.lastname: Narumi
authors.forename: Kenji
authors.initials: K
authors.lastname: Yasuoka
authors.forename: Masato
authors.initials: M
authors.lastname: Yasui
mesh_terms: D000818:Animals; D051401:Aquaporin 4 / Q000737:chemistry*; D001703:Biophysics / Q000379:methods; D002417:Cattle; D002462:Cell Membrane / Q000378:metabolism*; D008055:Lipids / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D056004:Molecular Dynamics Simulation; D011485:Protein Binding; D025941:Protein Interaction Mapping / Q000379:methods; D017434:Protein Structure, Tertiary; D011506:Proteins / Q000737:chemistry; D051381:Rats; D013816:Thermodynamics; D014867:Water / Q000737:chemistry
chemical_list: D051401:Aquaporin 4; D008055:Lipids; D011506:Proteins; D014867:Water