HIV-1 nuclear import in macrophages is regulated by CPSF6-capsid interactions at the Nuclear Pore Complex
- University of Heidelberg, Germany
Abstract
Nuclear entry of HIV-1 replication complexes through intact nuclear pore complexes is critical for successful infection. The host protein cleavage-and-polyadenylation-specificity-factor-6 (CPSF6) has been implicated in different stages of early HIV-1 replication. Applying quantitative microscopy of HIV-1 reverse-transcription and pre-integration-complexes (RTC/PIC), we show that CPSF6 is strongly recruited to nuclear replication complexes but absent from cytoplasmic RTC/PIC in primary human macrophages. Depletion of CPSF6 or lack of CPSF6 binding led to accumulation of HIV-1 subviral complexes at the nuclear envelope of macrophages and reduced infectivity. Two-color stimulated-emission-depletion microscopy indicated that under these circumstances HIV-1 complexes are retained inside the nuclear pore and undergo CA-multimer dependent CPSF6 clustering adjacent to the nuclear basket. We propose that nuclear entry of HIV-1 subviral complexes in macrophages is mediated by consecutive binding of Nup153 and CPSF6 to the hexameric CA lattice.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files for the plots of Figures 1,3,4 and supplemental material are provided.
Article and author information
Author details
Hans-Georg Kräusslich
Funding
Deutsche Forschungsgemeinschaft (SFB1129)
- Barbara Müller
- Hans-Georg Kräusslich
Deutsches Zentrum für Infektionsforschung (TTU HIV)
- Hans-Georg Kräusslich
Deutsche Forschungsgemeinschaft (SPP1923)
- Hans-Georg Kräusslich
Heidelberg Biosciences International Graduate School
- David Alejandro Bejarano
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Bejarano 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 nuclear import in macrophages is regulated by CPSF6-capsid interactions at the Nuclear Pore Complex
eLife 8:e41800.
https://doi.org/10.7554/eLife.41800
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