title: A C-terminal segment of the V1R vasopressin receptor is unstructured in the crystal structure of its chimera with the maltose-binding protein.
abstract: The V1 vascular vasopressin receptor (V1R) is a G-protein-coupled receptor (GPCR) involved in the regulation of body-fluid osmolality, blood volume and blood pressure. Signal transduction is mediated by the third intracellular loop of this seven-transmembrane protein as well as by the C-terminal cytoplasmic segment. A chimera of the maltose-binding protein (MBP) and the C-terminal segment of V1R has been cloned, expressed, purified and crystallized. The crystals belong to space group P2(1), with unit-cell parameters a = 51.10, b = 66.56, c = 115.72 A, beta = 95.99 degrees. The 1.8 A crystal structure reveals the conformation of MBP and part of the linker region of this chimera, with the C-terminal segment being unstructured. This may reflect a conformational plasticity in the C-terminal segment that may be necessary for proper function of V1R.
authors.affiliation: Department of Biochemistry, School of Medicine, Case Western Reserve University, Cleveland, OH 44106-4935, USA.
authors.forename: Nallini Vijayarangan
authors.initials: NV
authors.lastname: Adikesavan
authors.forename: Syed Saad
authors.initials: SS
authors.lastname: Mahmood
authors.forename: Nithianantham
authors.initials: N
authors.lastname: Stanley
authors.forename: Zhen
authors.initials: Z
authors.lastname: Xu
authors.forename: Nan
authors.initials: N
authors.lastname: Wu
authors.forename: Marc
authors.initials: M
authors.lastname: Thibonnier
authors.forename: Menachem
authors.initials: M
authors.lastname: Shoham
mesh_terms: D002352:Carrier Proteins / Q000737:chemistry* / Q000235:genetics; D003001:Cloning, Molecular; D018360:Crystallography, X-Ray; D006801:Humans; D058619:Maltose-Binding Proteins; D010446:Peptide Fragments / Q000737:chemistry* / Q000235:genetics; D011487:Protein Conformation; D017483:Receptors, Vasopressin / Q000737:chemistry* / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000737:chemistry
chemical_list: D002352:Carrier Proteins; D058619:Maltose-Binding Proteins; D010446:Peptide Fragments; D017483:Receptors, Vasopressin; D011993:Recombinant Fusion Proteins