HIV-1 Recruits UPF1 but Excludes UPF2 to Promote Nucleocytoplasmic Export of the Genomic RNA.
Unspliced, genomic HIV-1 RNA (vRNA) is a component of several ribonucleoprotein complexes (RNP) during the viral replication cycle. In earlier work, we demonstrated that the host upframeshift protein 1 (UPF1), a key factor in nonsense-mediated mRNA decay (NMD), colocalized and associated to the viral structural protein Gag during viral egress. In this work, we demonstrate a new function for UPF1 in the regulation of vRNA nuclear export. OPEN ACCESS Biomolecules 2015, 5 2809 We establish that the nucleocytoplasmic shuttling of UPF1 is required for this function and demonstrate that UPF1 exists in two essential viral RNPs during the late phase of HIV-1 replication: the first, in a nuclear export RNP that contains Rev, CRM1, DDX3 and the nucleoporin p62, and the second, which excludes these nuclear export markers but contains Gag in the cytoplasm. Interestingly, we observed that both UPF2 and the long isoform of UPF3a, UPF3aL, but not the shorter isoforms UPF3aS and UPF3b, are excluded from the UPF1-Rev-CRM1-DDX3 complex as they are negative regulators of vRNA nuclear export. In silico protein-protein docking analyses suggest that Rev binds UPF1 in a region that overlaps the UPF2 binding site, thus explaining the exclusion of this negative regulatory factor by HIV-1 that is necessary for vRNA trafficking. This work uncovers a novel and unique regulatory circuit involving several UPF proteins that ultimately regulate vRNA nuclear export and trafficking.
HIV-1 RNA Trafficking Laboratory, Lady Davis Institute for Medical Research-Sir Mortimer B. Davis Jewish General Hospital, Montréal QC H3T 1E2, Canada. lara.ajamian@mail.mcgill.ca.|Department of Medicine, Division of Experimental Medicine, McGill University, Montréal QC H3A 2B4, Canada. lara.ajamian@mail.mcgill.ca.
Lara
L
Ajamian
HIV-1 RNA Trafficking Laboratory, Lady Davis Institute for Medical Research-Sir Mortimer B. Davis Jewish General Hospital, Montréal QC H3T 1E2, Canada. karen_abel@gmx.de.|Department of Microbiology and Immunology, McGill University, Montréal QC H3T 1E2, Canada. karen_abel@gmx.de.
Karen
K
Abel
HIV-1 RNA Trafficking Laboratory, Lady Davis Institute for Medical Research-Sir Mortimer B. Davis Jewish General Hospital, Montréal QC H3T 1E2, Canada. shringar.rao@mail.mcgill.ca.|Department of Microbiology and Immunology, McGill University, Montréal QC H3T 1E2, Canada. shringar.rao@mail.mcgill.ca.
Shringar
S
Rao
HIV-1 RNA Trafficking Laboratory, Lady Davis Institute for Medical Research-Sir Mortimer B. Davis Jewish General Hospital, Montréal QC H3T 1E2, Canada. kishanda.vyboh@mail.mcgill.ca.|Department of Microbiology and Immunology, McGill University, Montréal QC H3T 1E2, Canada. kishanda.vyboh@mail.mcgill.ca.
Kishanda
K
Vyboh
Laboratory of Molecular and Cellular Virology, Virology Program, Biomedical Sciences Institute, Faculty of Medicine, Universidad de Chile, Independencia 8389100, Santiago, Chile. franciscogarcia96@gmail.com.
Francisco
F
García-de-Gracia
Laboratory of Molecular and Cellular Virology, Virology Program, Biomedical Sciences Institute, Faculty of Medicine, Universidad de Chile, Independencia 8389100, Santiago, Chile. rsotorifo@med.uchile.cl.
Ricardo
R
Soto-Rifo
Department of Pediatric Oncology, Hematology and Immunology, Heidelberg 69120, Germany. andreas.kulozik@med.uni-heidelberg.de.|European Molecular Biology Laboratory, Partnership Unit, University of Heidelberg Molecular Medicine, Heidelberg 69117, Germany. andreas.kulozik@med.uni-heidelberg.de.
Andreas E
AE
Kulozik
Institute for Genetics, University of Cologne, Cologne 50674, Germany. ngehring@uni-koeln.de.
Niels H
NH
Gehring
HIV-1 RNA Trafficking Laboratory, Lady Davis Institute for Medical Research-Sir Mortimer B. Davis Jewish General Hospital, Montréal QC H3T 1E2, Canada. andrew.mouland@mcgill.ca.|Department of Medicine, Division of Experimental Medicine, McGill University, Montréal QC H3A 2B4, Canada. andrew.mouland@mcgill.ca.|Department of Microbiology and Immunology, McGill University, Montréal QC H3T 1E2, Canada. andrew.mouland@mcgill.ca.
Andrew J
AJ
Mouland
D021581:Active Transport, Cell Nucleus; D002467:Cell Nucleus / Q000378:metabolism* / Q000821:virology; D053487:DEAD-box RNA Helicases / Q000378:metabolism; D015497:HIV-1 / Q000378:metabolism / Q000502:physiology*; D006367:HeLa Cells; D006801:Humans; D028884:Karyopherins / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000378:metabolism; D028861:Nuclear Pore Complex Proteins / Q000378:metabolism; D011485:Protein Binding; D020365:RNA Helicases; D012367:RNA, Viral / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism; D057074:Virus Release; D014779:Virus Replication; D054321:rev Gene Products, Human Immunodeficiency Virus / Q000378:metabolism; D000097606:Exportin 1 Protein
D053487:DEAD-box RNA Helicases; D028884:Karyopherins; D008562:Membrane Glycoproteins; D028861:Nuclear Pore Complex Proteins; D020365:RNA Helicases; D012367:RNA, Viral; D016601:RNA-Binding Proteins; D018160:Receptors, Cytoplasmic and Nuclear; D015534:Trans-Activators; D014157:Transcription Factors; D054321:rev Gene Products, Human Immunodeficiency Virus; D000097606:Exportin 1 Protein; C468286:UPF2 protein, human; C435487:UPF3A protein, human; C049312:nuclear pore protein p62; C119332:DDX3X protein, human; C101828:UPF1 protein, human
HIV-1; UPF1; nonsense mediated decay; nuclear RNA export; ribonucleoprotein; viral evasion