Novel Labeling Strategy for Automated Detection of Single Virus Fusion and Assessment of HIV-1 Protease Activity in Single Virions

A common approach to visualizing single-virus fusion utilizes a fluorescently labeled Gag that, upon processing by HIV-1 viral protease, yields fluid-phase fluorescent proteins trapped within the virus particle. Upon loss of viral membrane integrity this content marker rapidly diffuses out of the particle, and, in combination with a viral core fiducial, such as a fluorescently tagged Vpr, can be used to reliably report single-particle fusion....