Human nucleoporins promote HIV-1 docking at the nuclear pore, nuclear import and integration.
The nuclear pore complex (NPC) mediates nucleo-cytoplasmic transport of macromolecules and is an obligatory point of passage and functional bottleneck in the replication of some viruses. The Human Immunodeficiency Virus (HIV) has evolved the required mechanisms for active nuclear import of its genome through the NPC. However the mechanisms by which the NPC allows or even assists HIV translocation are still unknown. We investigated the involvement of four key nucleoporins in HIV-1 docking, translocation, and integration: Nup358/RanBP2, Nup214/CAN, Nup98 and Nup153. Although all induce defects in infectivity when depleted, only Nup153 actually showed any evidence of participating in HIV-1 translocation through the nuclear pore. We show that Nup358/RanBP2 mediates docking of HIV-1 cores on NPC cytoplasmic filaments by interacting with the cores and that the C-terminus of Nup358/RanBP2 comprising a cyclophilin-homology domain contributes to binding. We also show that Nup214/CAN and Nup98 play no role in HIV-1 nuclear import per se: Nup214/CAN plays an indirect role in infectivity read-outs through its effect on mRNA export, while the reduction of expression of Nup98 shows a slight reduction in proviral integration. Our work shows the involvement of nucleoporins in diverse and functionally separable steps of HIV infection and nuclear import.
Molecular Virology and Vaccinology Unit, CNRS URA 3015, Department of Virology, Institut Pasteur, Paris, France.
Francesca
F
Di Nunzio
Anne
A
Danckaert
Thomas
T
Fricke
Patricio
P
Perez
Juliette
J
Fernandez
Emmanuelle
E
Perret
Pascal
P
Roux
Spencer
S
Shorte
Pierre
P
Charneau
Felipe
F
Diaz-Griffero
Nathalie J
NJ
Arhel
D021581:Active Transport, Cell Nucleus / Q000235:genetics / Q000502:physiology; D015658:HIV Infections / Q000821:virology; D015497:HIV-1 / Q000378:metabolism* / Q000502:physiology; D006367:HeLa Cells; D006801:Humans; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism; D022022:Nuclear Pore / Q000378:metabolism*; D028861:Nuclear Pore Complex Proteins / Q000235:genetics / Q000378:metabolism*; D011485:Protein Binding / Q000235:genetics / Q000502:physiology
D018832:Molecular Chaperones; D028861:Nuclear Pore Complex Proteins; C094493:ran-binding protein 2