Figure 2. HIV-1 particles produced in IP5/IP6-depleted cells display aberrant morphology and lack a condensed capsid.

(A-C) Cryo-ET on indicated HIV-1 mutants produced in IPMK or IPPK KO cells with Minpp1 overexpression. Tilt series were collected and reconstructions performed to assess capsid morphology. A total of 131 WT, 34 IPPK + FM1 and 48 IPMK + FM1 particles were analysed. (A) Virions were classified into the indicated categories: Immature (pink), Mature Conical (dark blue), Mature Tubular (light blue), Mature Irregular (green). Slices through representative tomograms of the virions are shown together with quantification. Scale bars, 100 nm. (B) Virions with mature lattices were further subdivided into: Multiple Cores (green), Single Cores (cyan), Cores with additional closed structure (orange), Cores with additional open structure (light orange), Multilayered Cores (blue). Slices through example tomograms of the virions are shown together with quantification. Scale bars, 100 nm. (C) All particles that were categorized as VSV-G positive (as indicated by the spikes on the surface of the particles) on the grid but did not contain a clear assembled lattice were categorized into: Virions (black), Partial density (gray), Empty (orange), Structured density (blue), Filament structures (dark pink), Partial density (light pink). Slices through representative tomograms of the virions are shown together with quantification. Scale bars, 100 nm. (D) Thin-section electron-microscopy of HIV-1 virions produced in 293T cells or IPMK KO cells over-expressing Minpp1. Scale bar = 120 nm.