Capsid-Labelled HIV To Investigate the Role of Capsid during Nuclear Import and Integration
Irena Zurnic Bönisch, Lieve Dirix, Veerle Lemmens, Doortje Borrenberghs, Flore De Wit, Frank Vernaillen, Susana Rocha, Frauke Christ, Jelle Hendrix, Johan Hofkens, Zeger Debyser
Abstract
HIV-1 capsid protein (CA) builds a conical shell protecting viral genomic RNA inside the virus particles. Upon entry into host cells, this shell disassembles in a process of uncoating, which is coordinated with reverse transcription of viral RNA into DNA. After uncoating, a portion of CA remains associated with the viral DNA and mediates its nuclear import and, potentially, integration into host DNA. In this study, we tagged CA with eGFP to follow its trafficking in host cells and address potential CA roles in the nucleus. We found that while functional viruses import the tagged CA into the nucleus, this capsid protein is not part of integration-competent complexes. The roles of nuclear CA thus remain to be established.