title: Structural determination of virus protein U from HIV-1 by NMR in membrane environments.
abstract: Virus protein U (Vpu) from HIV-1, a small membrane protein composed of a transmembrane helical domain and two α-helices in an amphipathic cytoplasmic domain, down modulates several cellular proteins, including CD4, BST-2/CD317/tetherin, NTB-A, and CCR7. The interactions of Vpu with these proteins interfere with the immune system and enhance the release of newly synthesized virus particles. It is essential to characterize the structure and dynamics of Vpu in order to understand the mechanisms of the protein-protein interactions, and potentially to discover antiviral drugs. In this article, we describe investigations of the cytoplasmic domain of Vpu as well as full-length Vpu by NMR spectroscopy. These studies are complementary to earlier analysis of the transmembrane domain of Vpu. The results suggest that the two helices in the cytoplasmic domain form a U-shape. The length of the inter-helical loop in the cytoplasmic domain and the orientation of the third helix vary with the lipid composition, which demonstrate that the C-terminal helix is relatively flexible, providing accessibility for interaction partners.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093-0307.
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093-0307.
authors.forename: Eugene C
authors.initials: EC
authors.lastname: Lin
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093-0307.
authors.forename: Bibhuti B
authors.initials: BB
authors.lastname: Das
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093-0307.|Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA.
authors.forename: Ye
authors.initials: Y
authors.lastname: Tian
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093-0307.
authors.forename: Stanley J
authors.initials: SJ
authors.lastname: Opella
mesh_terms: D002462:Cell Membrane / Q000737:chemistry* / Q000378:metabolism / Q000821:virology; D002942:Circular Dichroism; D004058:Diffusion; D004134:Dimyristoylphosphatidylcholine / Q000737:chemistry; D015497:HIV-1 / Q000378:metabolism / Q000502:physiology; D054298:Human Immunodeficiency Virus Proteins / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008565:Membrane Proteins / Q000737:chemistry* / Q000378:metabolism; D008823:Micelles; D008958:Models, Molecular; D010742:Phospholipid Ethers / Q000737:chemistry; D011485:Protein Binding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D011510:Proteolipids / Q000737:chemistry; D054334:Viral Regulatory and Accessory Proteins / Q000737:chemistry* / Q000378:metabolism; D000086082:Viroporin Proteins
chemical_list: D004134:Dimyristoylphosphatidylcholine; D054298:Human Immunodeficiency Virus Proteins; D008565:Membrane Proteins; D008823:Micelles; D010742:Phospholipid Ethers; D011510:Proteolipids; D054334:Viral Regulatory and Accessory Proteins; C052298:1,2-dihexadecyl-sn-glycero-3-phosphocholine; C020485:proteoliposomes; C514859:vpu protein, Human immunodeficiency virus 1; D000086082:Viroporin Proteins
keywords: Human immunodeficiency virus (HIV); Lipid bilayers; Membrane protein; Nuclear magnetic resonance (NMR); Viral protein U (Vpu)