Fab-based inhibitors reveal ubiquitin independent functions for HIV Vif neutralization of APOBEC3 restriction factors.
The lentiviral protein Viral Infectivity Factor (Vif) counteracts the antiviral effects of host APOBEC3 (A3) proteins and contributes to persistent HIV infection. Vif targets A3 restriction factors for ubiquitination and proteasomal degradation by recruiting them to a multi-protein ubiquitin E3 liga...
| Main Authors: | , , , , , , , , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Public Library of Science (PLoS)
2018-01-01
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| Series: | PLoS Pathogens |
| Online Access: | https://doi.org/10.1371/journal.ppat.1006830 |
| _version_ | 1818361142932668416 |
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| author | Jennifer M Binning Amber M Smith Judd F Hultquist Charles S Craik Nathalie Caretta Cartozo Melody G Campbell Lily Burton Florencia La Greca Michael J McGregor Hai M Ta Koen Bartholomeeusen B Matija Peterlin Nevan J Krogan Natalia Sevillano Yifan Cheng John D Gross |
| author_facet | Jennifer M Binning Amber M Smith Judd F Hultquist Charles S Craik Nathalie Caretta Cartozo Melody G Campbell Lily Burton Florencia La Greca Michael J McGregor Hai M Ta Koen Bartholomeeusen B Matija Peterlin Nevan J Krogan Natalia Sevillano Yifan Cheng John D Gross |
| author_sort | Jennifer M Binning |
| collection | DOAJ |
| description | The lentiviral protein Viral Infectivity Factor (Vif) counteracts the antiviral effects of host APOBEC3 (A3) proteins and contributes to persistent HIV infection. Vif targets A3 restriction factors for ubiquitination and proteasomal degradation by recruiting them to a multi-protein ubiquitin E3 ligase complex. Here, we describe a degradation-independent mechanism of Vif-mediated antagonism that was revealed through detailed structure-function studies of antibody antigen-binding fragments (Fabs) to the Vif complex. Two Fabs were found to inhibit Vif-mediated A3 neutralization through distinct mechanisms: shielding A3 from ubiquitin transfer and blocking Vif E3 assembly. Combined biochemical, cell biological and structural studies reveal that disruption of Vif E3 assembly inhibited A3 ubiquitination but was not sufficient to restore its packaging into viral particles and antiviral activity. These observations establish that Vif can neutralize A3 family members in a degradation-independent manner. Additionally, this work highlights the potential of Fabs as functional probes, and illuminates how Vif uses a multi-pronged approach involving both degradation dependent and independent mechanisms to suppress A3 innate immunity. |
| first_indexed | 2024-12-13T21:11:59Z |
| format | Article |
| id | doaj.art-7095456598e14d2cb94a7e382671d584 |
| institution | Directory Open Access Journal |
| issn | 1553-7366 1553-7374 |
| language | English |
| last_indexed | 2024-12-13T21:11:59Z |
| publishDate | 2018-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS Pathogens |
| spelling | doaj.art-7095456598e14d2cb94a7e382671d5842022-12-21T23:31:19ZengPublic Library of Science (PLoS)PLoS Pathogens1553-73661553-73742018-01-01141e100683010.1371/journal.ppat.1006830Fab-based inhibitors reveal ubiquitin independent functions for HIV Vif neutralization of APOBEC3 restriction factors.Jennifer M BinningAmber M SmithJudd F HultquistCharles S CraikNathalie Caretta CartozoMelody G CampbellLily BurtonFlorencia La GrecaMichael J McGregorHai M TaKoen BartholomeeusenB Matija PeterlinNevan J KroganNatalia SevillanoYifan ChengJohn D GrossThe lentiviral protein Viral Infectivity Factor (Vif) counteracts the antiviral effects of host APOBEC3 (A3) proteins and contributes to persistent HIV infection. Vif targets A3 restriction factors for ubiquitination and proteasomal degradation by recruiting them to a multi-protein ubiquitin E3 ligase complex. Here, we describe a degradation-independent mechanism of Vif-mediated antagonism that was revealed through detailed structure-function studies of antibody antigen-binding fragments (Fabs) to the Vif complex. Two Fabs were found to inhibit Vif-mediated A3 neutralization through distinct mechanisms: shielding A3 from ubiquitin transfer and blocking Vif E3 assembly. Combined biochemical, cell biological and structural studies reveal that disruption of Vif E3 assembly inhibited A3 ubiquitination but was not sufficient to restore its packaging into viral particles and antiviral activity. These observations establish that Vif can neutralize A3 family members in a degradation-independent manner. Additionally, this work highlights the potential of Fabs as functional probes, and illuminates how Vif uses a multi-pronged approach involving both degradation dependent and independent mechanisms to suppress A3 innate immunity.https://doi.org/10.1371/journal.ppat.1006830 |
| spellingShingle | Jennifer M Binning Amber M Smith Judd F Hultquist Charles S Craik Nathalie Caretta Cartozo Melody G Campbell Lily Burton Florencia La Greca Michael J McGregor Hai M Ta Koen Bartholomeeusen B Matija Peterlin Nevan J Krogan Natalia Sevillano Yifan Cheng John D Gross Fab-based inhibitors reveal ubiquitin independent functions for HIV Vif neutralization of APOBEC3 restriction factors. PLoS Pathogens |
| title | Fab-based inhibitors reveal ubiquitin independent functions for HIV Vif neutralization of APOBEC3 restriction factors. |
| title_full | Fab-based inhibitors reveal ubiquitin independent functions for HIV Vif neutralization of APOBEC3 restriction factors. |
| title_fullStr | Fab-based inhibitors reveal ubiquitin independent functions for HIV Vif neutralization of APOBEC3 restriction factors. |
| title_full_unstemmed | Fab-based inhibitors reveal ubiquitin independent functions for HIV Vif neutralization of APOBEC3 restriction factors. |
| title_short | Fab-based inhibitors reveal ubiquitin independent functions for HIV Vif neutralization of APOBEC3 restriction factors. |
| title_sort | fab based inhibitors reveal ubiquitin independent functions for hiv vif neutralization of apobec3 restriction factors |
| url | https://doi.org/10.1371/journal.ppat.1006830 |
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