Core structure of the envelope glycoprotein GP2 from Ebola virus at 1.9-Å resolution

• DOI: 10.1073/pnas.96.6.2662
• Publication Date: 2002-07-26T14:42:40Z
• Authors: Vladimir N. Malas...; Brian J. Schneider; Margaret L. McNally; Michael A. Milhollen; James X. Pang; Peter S. Kim
• Keywords: Ectodomain; Heptad repeat; Antiparallel (mathematics); Viral membrane; Coiled coil

Ebola virions contain a surface transmembrane glycoprotein (GP) that is responsible for binding to target cells and subsequent fusion of the viral host-cell membranes. GP expressed as single-chain precursor posttranslationally processed into disulfide-linked fragments GP1 GP2. The GP2 subunit thought mediate membrane fusion. A soluble fragment ectodomain, lacking fusion-peptide region helix, folds stable, highly helical structure in aqueous solution. Limited proteolysis studies identify stable core ectodomain. This 74-residue core, denoted Ebo-74, was crystallized, its x-ray determined at 1.9-Å resolution. Ebo-74 forms trimer which long, central three-stranded coiled coil surrounded by shorter C-terminal helices are packed an antiparallel orientation hydrophobic grooves on coil. Our results confirm previously anticipated structural similarity between ectodomain from oncogenic retroviruses. likely represents fusion-active conformation protein, overall architecture resembles several other membrane-fusion proteins, including those HIV influenza.