Effects of inner nuclear membrane proteins SUN1/UNC-84A and SUN2/UNC- 84B on the early steps of HIV-1 infection

Torsten Schaller*, Lorenzo Bulli, Darja Pollpeter, Gilberto Betancor, Juliane Kutzner, Luis Apolonia, Nikolas Herold, Robin Burk, Michael H. Malim

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

17 Citations (Scopus)
265 Downloads (Pure)


Human immunodeficiency virus type 1 (HIV-1) infection of dividing and nondividing cells involves regulatory interactions with the nuclear pore complex (NPC), followed by translocation to the nucleus and preferential integration into genomic areas in proximity to the inner nuclear membrane (INM). To identify host proteins that may contribute to these processes, we performed an overexpression screen of known membrane-associated NE proteins. We found that the integral transmembrane proteins SUN1/UNC84A and SUN2/UNC84B are potent or modest inhibitors of HIV-1 infection, respectively, and that suppression corresponds to defects in the accumulation of viral cDNA in the nucleus. While laboratory strains (HIV-1NL4.3 and HIV-1IIIB) are sensitive to SUN1-mediated inhibition, the transmitted founder viruses RHPA and ZM247 are largely resistant. Using chimeric viruses, we identified the HIV-1 capsid (CA) protein as a major determinant of sensitivity to SUN1, and in vitroassembled capsid-nucleocapsid (CANC) nanotubes captured SUN1 and SUN2 from cell lysates. Finally, we generated SUN1-/- and SUN2-/- cells by using CRISPR/Cas9 and found that the loss of SUN1 had no effect on HIV-1 infectivity, whereas the loss of SUN2 had a modest suppressive effect. Taken together, these observations suggest that SUN1 and SUN2 may function redundantly to modulate postentry,nuclearassociated steps of HIV-1 infection.

Original languageEnglish
Article numbere00463-17
JournalJournal of Virology
Issue number19
Early online date26 Jul 2017
Publication statusPublished - 1 Oct 2017


  • CA
  • Cyclophilin A
  • Early infection
  • HIV-1
  • Nuclear envelope
  • Nuclear import
  • Nuclear pore complex
  • SUN1
  • SUN2
  • Transmitted founder virus


Dive into the research topics of 'Effects of inner nuclear membrane proteins SUN1/UNC-84A and SUN2/UNC- 84B on the early steps of HIV-1 infection'. Together they form a unique fingerprint.

Cite this