Direct Fluorescence of Retroviral Capsid Proteins

We will outline the use of a bioluminescent molecule, green fluorescent protein (GFP) to study theproteins in living cells. Unlike immunofluorescence which provides a "snapshot" of the proteins in awith GFP can be continuously monitored by microscopy since the fluorescence requires no exogenous sucofactors. To study retrovirus replication, GFP will be fused to the virus product required for partpolyprotein. The ability of Gag to package foreign proteins into virus particles already has been detechnology has been termed Retrosecretion. The incorporation of Gag-GFP fusions into virus particlesmechanics of retrovirus assembly and cell entry to be viewed using fluorescence microscopy. The releparticles will also be monitored by spectrofluorometry and will be tested as an extracellular reportof eukaryotic promoters.