Observation of single influenza virus-cell fusion and measurement by fluorescence video microscopy.
AUTOR(ES)
Lowy, R J
RESUMO
We have used intensified video fluorescence microscopy and digital image processing to observe and quantitate influenza virus (A/PR8/34/H1N1) fusion to human erythrocyte membranes. Viruses labeled with the lipid probe octadecylrhodamine B (R18) were seen to undergo fluorescence dequenching and eventual disappearance after exposure to pH levels known to induce virus-cell membrane fusion. Quantitative intensity measurements of single individual particles were possible. From these fluorescence data it has been possible to calculate the fraction of R18 dye molecules transferred from the virus to the cell. The redistribution of the lipid probe upon fusion at pH 5.0 had a t1/2 of 46 s, longer than expected for a free-diffusion model. The R18 loss was approximately twice as fast at pH 5.0 as at pH 5.1. No obvious delay until the start of fluorescence dequenching was observed after the pH changes, suggesting that activation processes are faster than the time resolution, 1-5 s, of the current method.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=53581Documentos Relacionados
- Primary Virus-Cell Interactions in the Immuno-fluorescence Assay of Venezuelan Equine Encephalomyelitis Virus
- A 45,000-M(r) glycoprotein in the Sendai virus envelope triggers virus-cell fusion.
- VIRUS-CELL INTERACTION WITH A TUMOR-PRODUCING VIRUS*
- Antibodies to CD9, a Tetraspan Transmembrane Protein, Inhibit Canine Distemper Virus-Induced Cell-Cell Fusion but Not Virus-Cell Fusion
- Cleavage Inhibition of the Murine Coronavirus Spike Protein by a Furin-Like Enzyme Affects Cell-Cell but Not Virus-Cell Fusion