Fusion of Sendai virions with phosphatidylcholine-cholesterol liposomes reflects the viral activity required for fusion with biological membranes.
Sendai virus envelopes were reconstituted after solubilization of intact virions with either Triton X-100 or octylglucoside. Envelopes obtained from Triton X-100, but not from octylglucoside solubilized virions, were hemolytic and promoted cell-cell fusion. Fluorescence dequenching studies [using N-4-nitrobenzo-2-oxa-1,3-diazole phosphatidylethanolamine-bearing viral envelopes] revealed that both preparations fused with negatively charged phospholipids. Fusion with phosphatidylcholine (PC)/cholesterol (chol) liposomes was promoted only by the hemolytic viral envelopes. Fluorescence dequenching studies, using intact virions bearing octadecylrhodamine B chloride, revealed that intact virions fused with PC/chol as well as with negatively charged phospholipids. Only fusion with PC/chol liposomes was inhibited by phenylmethylsulfonyl fluoride and dithiothreitol, reagents which are known to block the viral ability to fuse with biological membranes.
D002784:Cholesterol / Q000378:metabolism*; D004229:Dithiothreitol / Q000494:pharmacology; D004563:Electrochemistry; D004910:Erythrocyte Membrane; D006801:Humans; D008081:Liposomes / Q000378:metabolism*; D008561:Membrane Fusion; D010222:Parainfluenza Virus 1, Human / Q000502:physiology*; D010664:Phenylmethylsulfonyl Fluoride / Q000494:pharmacology; D010713:Phosphatidylcholines / Q000378:metabolism*; D012995:Solubility; D013050:Spectrometry, Fluorescence; D014771:Virion / Q000502:physiology*
D008081:Liposomes; D010713:Phosphatidylcholines; D010664:Phenylmethylsulfonyl Fluoride; D002784:Cholesterol; D004229:Dithiothreitol