Secretion of a murine retroviral Env associated with resistance to infection.
Fv4 is an endogenous defective murine leukaemia virus (MuLV) which expresses high levels of an envelope protein (Env) closely related to that of the ecotropic class of MuLVs. Mice bearing the natural Fv4 gene or a transgenic version are resistant to infection by ecotropic MuLVs. Fv4 mice secrete the surface peptide (SU) of the Fv4 Env in their serum and this secreted Env can block infection of NIH3T3 cells. To study the secretion of Fv4, we metabolically labelled cells expressing Fv4 Env or Env from infectious MuLVs and followed synthesis, glycosylation, proteolytic processing and secretion of Env species. We found no difference in the kinetics of synthesis or processing of Fv4 Env compared to the envelopes of infectious MuLVs, but Fv4 Env associated more weakly with its transmembrane anchor and was shed from the surface of cells.
Nihrane
A
A
Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-0460, USA.
Lebedeva
I
I
Lyu
M S
MS
Fujita
K
K
Silver
J
J
D000818:Animals; D007113:Immunity, Innate / Q000235:genetics* / Q000276:immunology; D009052:Leukemia Virus, Murine / Q000378:metabolism*; D007942:Leukemia, Experimental / Q000276:immunology / Q000378:metabolism*; D008565:Membrane Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D012192:Retroviridae Infections / Q000276:immunology / Q000378:metabolism*; D014412:Tumor Virus Infections / Q000276:immunology / Q000378:metabolism*
C103555:Fv4 protein, mouse; D008565:Membrane Proteins