![]() |
|
|
Vol. 18, Issue 2, 414-425, February 2007
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||


*Cell Biology Unit, MRC-Laboratory for Molecular Cell Biology and Department of Biochemistry and Molecular Biology, University College London, London WC1E 6BT, United Kingdom; and
Hematology-Oncology Division, Department of Medicine, University of Pennsylvania, Philadelphia, PA 19104
Submitted June 19, 2006;
Revised November 3, 2006;
Accepted November 6, 2006
Monitoring Editor: Jean Gruenberg
During the assembly of enveloped viruses viral and cellular components essential for infectious particles must colocalize at specific membrane locations. For the human and simian immunodeficiency viruses (HIV and SIV), sorting of the viral envelope proteins (Env) to assembly sites is directed by trafficking signals located in the cytoplasmic domain of the transmembrane protein gp41 (TM). A membrane proximal conserved GYxxØ motif mediates endocytosis through interaction with the clathrin adaptor AP-2. However, experiments with SIVmac239 Env indicate the presence of additional signals. Here we show that a conserved C-terminal dileucine in HIVHxB2 also mediates endocytosis. Biochemical and morphological assays demonstrate that the C-terminal dileucine motif mediates internalization as efficiently as the GYxxØ motif and that both must be removed to prevent Env internalization. RNAi experiments show that depletion of the clathrin adaptor AP-2 leads to increased plasma membrane expression of HIV Env and that this adaptor is required for efficient internalization mediated by both signals. The redundancy of conserved endocytosis signals and the role of the SIVmac239 Env GYxxØ motif in SIV pathogenesis, suggest that these motifs have functions in addition to endocytosis, possibly related to Env delivery to the site of viral assembly and/or incorporation into budding virions.
Address correspondence to: Mark Marsh (m.marsh{at}ucl.ac.uk)
Abbreviations used: Env, envelope glycoprotein; gp, glycoprotein; HIV, human immunodeficiency virus; SIV, simian immunodeficiency virus; SU, surface subunit of the viral envelope glycoprotein; TM, transmembrane subunit of the viral envelope glycoprotein.
This article has been cited by other articles:
![]() |
S. H. Kim and T. A. Ryan A Distributed Set of Interactions Controls {micro}2 Functionality in the Role of AP-2 as a Sorting Adaptor in Synaptic Vesicle Endocytosis J. Biol. Chem., November 20, 2009; 284(47): 32803 - 32812. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Yue, L. Shang, and E. Hunter Truncation of the Membrane-Spanning Domain of Human Immunodeficiency Virus Type 1 Envelope Glycoprotein Defines Elements Required for Fusion, Incorporation, and Infectivity J. Virol., November 15, 2009; 83(22): 11588 - 11598. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Beaumont, D. Vendrame, B. Verrier, E. Roch, F. Biron, F. Barin, F. Mammano, and D. Brand Matrix and Envelope Coevolution Revealed in a Patient Monitored since Primary Infection with Human Immunodeficiency Virus Type 1 J. Virol., October 1, 2009; 83(19): 9875 - 9889. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Weng, D. N. Krementsov, S. Khurana, N. H. Roy, and M. Thali Formation of Syncytia Is Repressed by Tetraspanins in Human Immunodeficiency Virus Type 1-Producing Cells J. Virol., August 1, 2009; 83(15): 7467 - 7474. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Shang, L. Yue, and E. Hunter Role of the Membrane-Spanning Domain of Human Immunodeficiency Virus Type 1 Envelope Glycoprotein in Cell-Cell Fusion and Virus Infection J. Virol., June 1, 2008; 82(11): 5417 - 5428. [Abstract] [Full Text] [PDF] |
||||
![]() |
J.-H. Huang, Z. Qi, F. Wu, L. Kotula, S. Jiang, and Y.-H. Chen Interaction of HIV-1 gp41 Core with NPF Motif in Epsin: IMPLICATION IN ENDOCYTOSIS OF HIV J. Biol. Chem., May 30, 2008; 283(22): 14994 - 15002. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Jiang and C. Aiken Maturation-Dependent Human Immunodeficiency Virus Type 1 Particle Fusion Requires a Carboxyl-Terminal Region of the gp41 Cytoplasmic Tail J. Virol., September 15, 2007; 81(18): 9999 - 10008. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Deneka, A. Pelchen-Matthews, R. Byland, E. Ruiz-Mateos, and M. Marsh In macrophages, HIV-1 assembles into an intracellular plasma membrane domain containing the tetraspanins CD81, CD9, and CD53 J. Cell Biol., April 23, 2007; 177(2): 329 - 341. [Abstract] [Full Text] [PDF] |
||||