Single HIV-1 Imaging Reveals Progression of Infection through CA-Dependent Steps of Docking at the Nuclear Pore, Uncoating, and Nuclear Transport

Published on Apr 1, 2018in Cell Host & Microbe15.753
· DOI :10.1016/j.chom.2018.03.009
Ashwanth C. Francis5
Estimated H-index: 5
(Emory University),
Gregory B. Melikyan23
Estimated H-index: 23
(Emory University)
Summary The HIV-1 core consists of capsid proteins (CA) surrounding viral genomic RNA. After virus-cell fusion, the core enters the cytoplasm and the capsid shell is lost through uncoating. CA loss precedes nuclear import and HIV integration into the host genome, but the timing and location of uncoating remain unclear. By visualizing single HIV-1 infection, we find that CA is required for core docking at the nuclear envelope (NE), whereas early uncoating in the cytoplasm promotes proteasomal degradation of viral complexes. Only docked cores exhibiting accelerated loss of CA at the NE enter the nucleus. Interestingly, a CA mutation (N74D) altering virus engagement of host factors involved in nuclear transport does not alter the uncoating site at the NE but reduces the nuclear penetration depth. Thus, CA protects HIV-1 complexes from degradation, mediates docking at the nuclear pore before uncoating, and determines the depth of nuclear penetration en route to integration.
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We are grateful to Dr. J. Demeulemeester and Dr. J. De Rijck for critical reading and thank P. Van de Velde, B. Vanremoortel and NJ. Van der Veeken for their technical assistance. Viral vector production was performed at the Leuven Viral Vector Core. LEDGINs were synthesized by Cistim/CD3 (courtesy of Dr. A. Marchand). Personal fellowship from 'Agentschap voor Innovatie door Wetenschap en Technologie' [IWT 111595 to D.B.]; Personal fellowship from 'Fonds Wetenschappelijk Onderzoek' [FWO 11M0713N...
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