Endocytic Motif on a Biotin-Tagged HIV-1 Env Modulates the Co-Transfer of Env and Gag during Cell-to-Cell Transmission
During HIV-1 transmission through T cell virological synapses, the recruitment of the envelope (Env) glycoprotein to the site of cell–cell contact is important for adhesion and for packaging onto nascent virus particles which assemble at the site. Live imaging studies in CD4 T cells have captured th...
| Main Authors: | , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-08-01
|
| Series: | Viruses |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1999-4915/13/9/1729 |
| _version_ | 1797517003127259136 |
|---|---|
| author | María Inés Barría Raymond A. Alvarez Kenneth Law Deanna L. Wolfson Thomas Huser Benjamin K. Chen |
| author_facet | María Inés Barría Raymond A. Alvarez Kenneth Law Deanna L. Wolfson Thomas Huser Benjamin K. Chen |
| author_sort | María Inés Barría |
| collection | DOAJ |
| description | During HIV-1 transmission through T cell virological synapses, the recruitment of the envelope (Env) glycoprotein to the site of cell–cell contact is important for adhesion and for packaging onto nascent virus particles which assemble at the site. Live imaging studies in CD4 T cells have captured the rapid recruitment of the viral structural protein Gag to VSs. We explored the role of endocytic trafficking of Env initiated by a membrane proximal tyrosine motif during HIV transfer into target cells and examined the factors that allow Gag and Env to be transferred together across the synapse. To facilitate tracking of Env in live cells, we adapted an Env tagging method and introduced a biotin acceptor peptide (BAP) into the V4 loop of Env gp120, enabling sensitive fluorescent tracking of V4-biotinylated Env. The BAP-tagged and biotinylated HIVs were replication-competent in cell-free and cell-to-cell infection assays. Live cell fluorescent imaging experiments showed rapid internalized cell surface Env on infected cells. Cell–cell transfer experiments conducted with the Env endocytosis mutant (Y712A) showed increased transfer of Env. Paradoxically, this increase in Env transfer was associated with significantly reduced Gag transfer into target cells, when compared to viral transfer associated with WT Env. This Y712A Env mutant also exhibited an altered Gag/biotin Env fluorescence ratio during transfer that correlated with decreased productive cell-to-cell infection. These results may suggest that the internalization of Env into recycling pools plays an important role in the coordinated transfer of Gag and Env across the VS, which optimizes productive infection in target cells. |
| first_indexed | 2024-03-10T07:08:50Z |
| format | Article |
| id | doaj.art-9979ab062bf3421c900cfd22c4967d43 |
| institution | Directory Open Access Journal |
| issn | 1999-4915 |
| language | English |
| last_indexed | 2024-03-10T07:08:50Z |
| publishDate | 2021-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Viruses |
| spelling | doaj.art-9979ab062bf3421c900cfd22c4967d432023-11-22T15:37:06ZengMDPI AGViruses1999-49152021-08-01139172910.3390/v13091729Endocytic Motif on a Biotin-Tagged HIV-1 Env Modulates the Co-Transfer of Env and Gag during Cell-to-Cell TransmissionMaría Inés Barría0Raymond A. Alvarez1Kenneth Law2Deanna L. Wolfson3Thomas Huser4Benjamin K. Chen5Facultad de Medicina y Ciencia, Universidad San Sebastián, Puerto Montt 5501842, ChileDivision of Infectious Diseases, Department of Medicine, Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USADivision of Infectious Diseases, Department of Medicine, Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USADepartment of Physics and Technology, UiT the Arctic University of Norway, NO-9037 Tromsø, NorwayBiomolecular Photonics, Department of Physics, Bielefeld University, 33615 Bielefeld, GermanyFacultad de Medicina y Ciencia, Universidad San Sebastián, Puerto Montt 5501842, ChileDuring HIV-1 transmission through T cell virological synapses, the recruitment of the envelope (Env) glycoprotein to the site of cell–cell contact is important for adhesion and for packaging onto nascent virus particles which assemble at the site. Live imaging studies in CD4 T cells have captured the rapid recruitment of the viral structural protein Gag to VSs. We explored the role of endocytic trafficking of Env initiated by a membrane proximal tyrosine motif during HIV transfer into target cells and examined the factors that allow Gag and Env to be transferred together across the synapse. To facilitate tracking of Env in live cells, we adapted an Env tagging method and introduced a biotin acceptor peptide (BAP) into the V4 loop of Env gp120, enabling sensitive fluorescent tracking of V4-biotinylated Env. The BAP-tagged and biotinylated HIVs were replication-competent in cell-free and cell-to-cell infection assays. Live cell fluorescent imaging experiments showed rapid internalized cell surface Env on infected cells. Cell–cell transfer experiments conducted with the Env endocytosis mutant (Y712A) showed increased transfer of Env. Paradoxically, this increase in Env transfer was associated with significantly reduced Gag transfer into target cells, when compared to viral transfer associated with WT Env. This Y712A Env mutant also exhibited an altered Gag/biotin Env fluorescence ratio during transfer that correlated with decreased productive cell-to-cell infection. These results may suggest that the internalization of Env into recycling pools plays an important role in the coordinated transfer of Gag and Env across the VS, which optimizes productive infection in target cells.https://www.mdpi.com/1999-4915/13/9/1729HIV-1cell-to-cell transmissionvirological synapses (VSs)HIV envelopebiotin acceptor peptide |
| spellingShingle | María Inés Barría Raymond A. Alvarez Kenneth Law Deanna L. Wolfson Thomas Huser Benjamin K. Chen Endocytic Motif on a Biotin-Tagged HIV-1 Env Modulates the Co-Transfer of Env and Gag during Cell-to-Cell Transmission Viruses HIV-1 cell-to-cell transmission virological synapses (VSs) HIV envelope biotin acceptor peptide |
| title | Endocytic Motif on a Biotin-Tagged HIV-1 Env Modulates the Co-Transfer of Env and Gag during Cell-to-Cell Transmission |
| title_full | Endocytic Motif on a Biotin-Tagged HIV-1 Env Modulates the Co-Transfer of Env and Gag during Cell-to-Cell Transmission |
| title_fullStr | Endocytic Motif on a Biotin-Tagged HIV-1 Env Modulates the Co-Transfer of Env and Gag during Cell-to-Cell Transmission |
| title_full_unstemmed | Endocytic Motif on a Biotin-Tagged HIV-1 Env Modulates the Co-Transfer of Env and Gag during Cell-to-Cell Transmission |
| title_short | Endocytic Motif on a Biotin-Tagged HIV-1 Env Modulates the Co-Transfer of Env and Gag during Cell-to-Cell Transmission |
| title_sort | endocytic motif on a biotin tagged hiv 1 env modulates the co transfer of env and gag during cell to cell transmission |
| topic | HIV-1 cell-to-cell transmission virological synapses (VSs) HIV envelope biotin acceptor peptide |
| url | https://www.mdpi.com/1999-4915/13/9/1729 |
| work_keys_str_mv | AT mariainesbarria endocyticmotifonabiotintaggedhiv1envmodulatesthecotransferofenvandgagduringcelltocelltransmission AT raymondaalvarez endocyticmotifonabiotintaggedhiv1envmodulatesthecotransferofenvandgagduringcelltocelltransmission AT kennethlaw endocyticmotifonabiotintaggedhiv1envmodulatesthecotransferofenvandgagduringcelltocelltransmission AT deannalwolfson endocyticmotifonabiotintaggedhiv1envmodulatesthecotransferofenvandgagduringcelltocelltransmission AT thomashuser endocyticmotifonabiotintaggedhiv1envmodulatesthecotransferofenvandgagduringcelltocelltransmission AT benjaminkchen endocyticmotifonabiotintaggedhiv1envmodulatesthecotransferofenvandgagduringcelltocelltransmission |