Incorporation of simian virus 5 fusion protein into murine leukemia virus particles and its effect on the co-incorporation of retroviral envelope glycoproteins

We describe the generation of murine leukemia virus (MLV) virus particles c arrying the paramyxovirus fusion protein F from simian virus 5 (SV5-F). Thi s glycoprotein was expressed in cells providing Moloney MLV (MoMLV) Gag and Pol proteins and a lacZ retroviral vector. SV5-F was correctly expressed, processed, and efficiently incorporated into retroviral particles. SV5-F-be aring retroviruses were not infectious although a weak binding to primate a nd rodent cells could be detected and SV5-F could mediate cell to cell fusi on. We then co-expressed the SV5-F glycoprotein in retroviral particles wit h chimeric and wild-type MoMLV envelope glycoproteins. Our results show tha t F strongly inhibited infection via the retroviral envelopes although the mechanism of inhibition was different depending on the retroviral envelope used. (C) 2000 Academic Press.