HIV-1 uncoating by release of viral cDNA from capsid-like structures in the nucleus of infected cells
- University Hospital Heidelberg, Germany
Abstract
HIV-1 replication commences inside the cone-shaped viral capsid, but timing, localization and mechanism of uncoating are under debate. We adapted a strategy to visualize individual reverse-transcribed HIV-1 cDNA molecules and their association with viral and cellular proteins using fluorescence and correlative-light-and-electron-microscopy (CLEM). We specifically detected HIV-1 cDNA inside nuclei, but not in the cytoplasm. Nuclear cDNA initially co-localized with a fluorescent integrase fusion (IN-FP) and the viral CA (capsid) protein, but cDNA-punctae separated from IN-FP/CA over time. This phenotype was conserved in primary HIV-1 target cells, with nuclear HIV-1 complexes exhibiting strong CA-signals in all cell types. CLEM revealed cone-shaped HIV-1 capsid-like structures and apparently broken capsid-remnants at the position of IN-FP signals and elongated chromatin-like structures in the position of viral cDNA punctae lacking IN-FP. Our data argue for nuclear uncoating by physical disruption rather than cooperative disassembly of the CA-lattice, followed by physical separation from the pre-integration complex.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figure 1f,h, Figure 1 figure supplement 1c-d, Figure 1 figure supplement 3a, Figure 2a-b, Figure 2e-f, Figure 3b-c, Figure 4c,g,h,j-k,o, Figure 4 - figure supplement 1a-b, Figure 7c,e-f, Figure 7 - figure supplement 1b, Figure 7 - figure supplement 2a-b. Materials involving the ANCHOR system are MTA-restricted and commercially available from NeoVirTech (France).
Article and author information
Author details
Hans-Georg Kräusslich
Funding
Deutsche Forschungsgemeinschaft (Projektnummer 240245660 - SFB 1129 project 5)
- Thorsten G Müller
- Vojtech Zila
- Kyra Peters
- Hans-Georg Kräusslich
Deutsche Forschungsgemeinschaft (Projektnummer 240245660 - SFB 1129 project 6)
- Sandra Schifferdecker
- Barbara Müller
Deutsche Forschungsgemeinschaft (Projektnummer 240245660 - SFB 1129 project 20)
- Mia Stanic
- Bojana Lucic
- Marina Lusic
Deutsches Zentrum für Infektionsforschung (TTU HIV)
- Vibor Laketa
- Marina Lusic
- Hans-Georg Kräusslich
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Müller et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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HIV-1 uncoating by release of viral cDNA from capsid-like structures in the nucleus of infected cells
eLife 10:e64776.
https://doi.org/10.7554/eLife.64776
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