Abstract

Doc number: 17

Abstract

Background: Ankyrins are cellular mediators of a number of essential protein-protein interactions. Unlike intrabodies, ankyrins are composed of highly structured repeat modules characterized by disulfide bridge-independent folding. Artificial ankyrin molecules, designed to target viral components, might act as intracellular antiviral agents and contribute to the cellular immunity against viral pathogens such as HIV-1.

Results: A phage-displayed library of artificial ankyrins was constructed, and screened on a polyprotein made of the fused matrix and capsid domains (MA-CA) of the HIV-1 Gag precursor. An ankyrin with three modules named AnkGAG 1D4 (16.5 kDa) was isolated. AnkGAG 1D4 and MA-CA formed a protein complex with a stoichiometry of 1:1 and a dissociation constant of Kd ~ 1 μM, and the AnkGAG 1D4 binding site was mapped to the N-terminal domain of the CA, within residues 1-110. HIV-1 production in SupT1 cells stably expressing AnkGAG 1D4 in both N-myristoylated and non-N-myristoylated versions was significantly reduced compared to control cells. AnkGAG 1D4 expression also reduced the production of MLV, a phylogenetically distant retrovirus. The AnkGAG 1D4-mediated antiviral effect on HIV-1 was found to occur at post-integration steps, but did not involve the Gag precursor processing or cellular trafficking. Our data suggested that the lower HIV-1 progeny yields resulted from the negative interference of AnkGAG 1D4-CA with the Gag assembly and budding pathway.

Conclusions: The resistance of AnkGAG 1D4-expressing cells to HIV-1 suggested that the CA-targeted ankyrin AnkGAG 1D4 could serve as a protein platform for the design of a novel class of intracellular inhibitors of HIV-1 assembly based on ankyrin-repeat modules.

Details

Title
Antiviral activity of recombinant ankyrin targeted to the capsid domain of HIV-1 Gag polyprotein
Author
Nangola, Sawitree; Urvoas, Agathe; Valerio-Lepiniec, Marie; Khamaikawin, Wannisa; Sakkhachornphop, Supachai; Hong, Saw-See; Boulanger, Pierre; Minard, Philippe; Tayapiwatana, Chatchai
Pages
17
Publication year
2012
Publication date
2012
Publisher
BioMed Central
e-ISSN
17424690
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
929145441
Copyright
© 2012 Nangola et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.