Abstract
Human apolipoprotein-B mRNA-editing catalytic polypeptide-like 3G (A3G) is a cytidine deaminase that restricts retroviruses, endogenous retro-elements and DNA viruses. A3G plays a key role in the anti-HIV-1 innate cellular immunity. The HIV-1 Vif protein counteracts A3G mainly by leading A3G towards the proteosomal machinery and by direct inhibition of its enzymatic activity. Both activities involve direct interaction between Vif and A3G. Disrupting the interaction between A3G and Vif may rescue A3G antiviral activity and inhibit HIV-1 propagation. Here, mapping the interaction sites between A3G and Vif by peptide array screening revealed distinct regions in Vif important for A3G binding, including the N-terminal domain (NTD), C-terminal domain (CTD) and residues 83-99. The Vif-binding sites in A3G included 12 different peptides that showed strong binding to either full-length Vif, Vif CTD or both. Sequence similarity was found between Vif-binding peptides from the A3G CTD and NTD. A3G peptides were synthesized and tested for their ability to counteract Vif action. A3G 211-225 inhibited HIV-1 replication in cell culture and impaired Vif dependent A3G degradation. In vivo co-localization of full-length Vif with A3G 211-225 was demonstrated by use of FRET. This peptide has the potential to serve as an anti-HIV-1 lead compound. Our results suggest a complex interaction between Vif and A3G that is mediated by discontinuous binding regions with different affinities.
| Original language | English |
|---|---|
| Pages (from-to) | 3523-3532 |
| Number of pages | 10 |
| Journal | Bioorganic and Medicinal Chemistry |
| Volume | 21 |
| Issue number | 12 |
| DOIs | |
| State | Published - 15 Jun 2013 |
Bibliographical note
Funding Information:T.H.R. was partly supported by the Fulbright Foundation and the ISEF Foundation .
Funding Information:
This project is funded in whole or in part with Federal funds from the National Cancer Institute, National Institutes of Health, under contract number HHSN261200800001E. The content of this publication does not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S. Government. This research was supported (in part) by the Intramural Research Program of the NIH, National Cancer Institute, Center for Cancer Research, Frederick National Lab. Further funding was provided by grants from the NIH Intramural AIDS Targeted Antiviral Program (IATAP) and the NIAID Intramural Biodefense Research Program.
Funding Information:
The pcDNA-HVif plasmid was provided by the NIH AIDS Research and Reference Reagent Program, Division of AIDS, NIAID, NIH 78
Funding Information:
This work was supported by the US-Israel Binational Science Foundation (BSF) and by Grants from the National Institutes of Health ( P01 GM091743 to R.S.H. with a subaward to M.K.).
Funding Information:
J.H. was supported by NIST Innovation in Measurement Science program on “Optical Medical Imaging for Clinical Applications.” J.L. held National Research Council Research Associateship supported by NIH (NIBIB)/NIST . Funding for these awards was provided by and the intramural program of the National Institute for Biomedical Imaging and Bioengineering of the NIH.
Keywords
- A3G
- Apobec-3G
- HIV-1
- Peptide arrays
- Protein-protein interactions
- Vif
