Figure 2.

CryoEM imaging of single HIV-1 particles within a HeLa cell by correlative microscopy. (A) An overview differential interference contrast (DIC) image (10 ×) of HeLa cells cultured on an index gold EM grid and infected with HIV-1 particles pseudotyped with VSV-G and containing GFP-Vpr. (B & C) DIC images of a selected area (red box in A) recorded with 10 × (B) or 60 × (C) objective lenses. Inset in C shows the raw GFP signals which were pseudocolored in red and overlaid on the DIC image in C. (D – F) Low dose cryoEM images of the corresponding region in the DIC image (white box in (C)) containing a single GFP-labeled virus particle at nominal magnifications of 170 × (D), 3,500 × (E) and 50,000 × (F). The boxed region corresponds to the image frame in the adjacent panel. In F, an HIV-1 particle with a conical-shaped core (arrow) is clearly visible inside a multi-vesicular body (MVB). Scale bars, 50 μm in A – D, 2 μm in E and 0.1 μm in F. See also movie S1 and Figure S1.