Cholesterol modulates the fusogenic activity of a membranotropic domain of the FIV glycoprotein gp36(706 views) Vitiello G, Fragneto G, Petruk AA, Falanga A, Galdiero S, D'Ursi A, Merlino A, D'Errico G
Department of Chemical Sciences, University of Naples Federico II, Naples, Italy
CSGI (Consorzio per Lo Sviluppo Dei Sistemi A Grande Interfase), Florence, Italy
Institut Laue-Langevin, Grenoble, France
Departamento de Química Inorgánica, Analítica y Química Física, INQUIMAE-CONICET, University of Buenos Aires, Buenos Aires, Argentina
Department of Pharmacy, Centro Interuniversitario di Ricerca sui Peptidi Bioattivi, University of Naples Federico II, Naples, Italy
Istituto di Biostrutture e Bioimmagini, CNR, Naples, Italy
Departamento de Qu mica Inorg nica, Anal tica y Qu mica F sica, INQUIMAE-CONICET, University of Buenos Aires, Buenos Aires, Argentina
References: Not available.
Cholesterol modulates the fusogenic activity of a membranotropic domain of the FIV glycoprotein gp36
Lipid composition of viral envelopes is usually rich in sphingolipids and cholesterol (CHOL). These components have a stiffening effect on the membrane, thus enhancing the energetic barrier to be overcome for its fusion with the T-cell plasma membrane, a fundamental step of the infection process. In this work, we demonstrate that the octapeptide (C8) corresponding to the Trp(770)-Ile(777) sequence of the Feline Immunodeficiency Virus gp36 is highly effective in inducing the fusion of palmitoyl oleoyl phosphatidylcholine (POPC)/sphingomyelin (SM)/CHOL membranes. We analyze the molecular mechanism of the C8-membrane interactions combining Neutron Reflectivity (NR) and Electron Spin Resonance (ESR) experiments, and molecular dynamics simulations. A strict interplay among the different lipids in the peptide-induced fusion mechanism is highlighted. Since CHOL preferentially locates close to SM, POPC molecules remain relatively free to interact with the peptide, driving its positioning at the membrane interface. Here, C8 comes in contact with CHOL-interacting SM molecules, causing a strong perturbation of acyl chain ordering, which is a necessary condition for membrane fusion. Our findings suggest that CHOL rules, by an indirect mechanism, the activity of viral fusion glycoproteins.
Cholesterol modulates the fusogenic activity of a membranotropic domain of the FIV glycoprotein gp36