Particle assembly and Vpr expression in human immunodeficiency virus type 1-infected cells demonstrated by immunoelectron microscopy

Biochemical and Structural Analysis of Isolated Mature Cores of Human Immunodeficiency Virus Type 1

“…The accessory protein Vpr was found significantly enriched in core preparations, supporting its postulated role in transport of the HIV-1 preintegration complex to the nucleus (4,22,26). Using immuno-EM analysis, Wang et al (54) detected Vpr primarily underneath the membrane and not in the core of HIV-1. However, these virions were mostly immature, and the quality of the immuno-EM images is insufficient to determine the precise localization of the protein.…”

“…Most of our current understanding of the molecular organization of HIV-1 is derived from immuno-EM studies of complete virions (8,14,18,34,54), from biochemical fractionation of subviral components (4,26,33), and by analogy with other members of the family (reviewed in reference 52). Because of the inherent instability of the HIV-1 core, detailed characterization of its morphology and molecular architecture has not been performed.…”

Independent Segregation of Human Immunodeficiency Virus Type 1 Gag Protein Complexes and Lipid Rafts

“…Following fixation and sectioning, analysis was performed on a Philips CM-12 electron microscope equipped with a high-resolution charge-coupled device camera. For immunoelectron microscopic analysis, pellets were embedded using LR white or Eponate as described previously (38,39). In brief, thin sections (100 nm thick) were etched with freshly made 5% H 2 O 2 and incubated with anti-MA rabbit antiserum (36).…”

Incorporation of Vpr into Human Immunodeficiency Virus Type 1 Requires a Direct Interaction with the p6 Domain of the p55 Gag Precursor

“…The localization of Vpr and Vpx within virions is still unclear. Immunoelectron microscopic studies suggested that the HIV-1 Vpr protein localized beneath the viral envelope, co-localizing with the Gag p24 core structures (21). However, a more recent analysis by Kewalramani and Emerman (22) placed the Vpx protein within HIV-2 cores.…”