Open AccessMapping the Binding Interface between an HIV-1 Inhibiting Intrabody and the Viral Protein Rev
Author(s) -
Thomas Vercruysse,
Eline Boons,
Tom Venken,
Els Vanstreels,
Arnout Voet,
Jan Steyaert,
Marc De Maeyer,
Dirk Daelemans
Publication year - 2013
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0060259
Subject(s) - paratope , alanine scanning , epitope , protein–protein interaction , docking (animal) , mutant , viral protein , microbiology and biotechnology , in silico , function (biology) , biology , chemistry , computational biology , plasma protein binding , intracellular , antibody , virology , biochemistry , genetics , mutagenesis , gene , virus , medicine , nursing
HIV-1 Rev is the key protein in the nucleocytoplasmic export and expression of the late viral mRNAs. An important aspect for its function is its ability to multimerize on these mRNAs. We have recently identified a llama single-domain antibody (Nb 190 ) as the first inhibitor targeting the Rev multimerization function in cells. This nanobody is a potent intracellular antibody that efficiently inhibits HIV-1 viral production. In order to gain insight into the Nb 190 -Rev interaction interface, we performed mutational and docking studies to map the interface between the nanobody paratope and the Rev epitope. Alanine mutants of the hyper-variable domains of Nb 190 and the Rev multimerization domains were evaluated in different assays measuring Nb 190 -Rev interaction or viral production. Seven residues within Nb 190 and five Rev residues are demonstrated to be crucial for epitope recognition. These experimental data were used to perform docking experiments and map the Nb 190 -Rev structural interface. This Nb 190 -Rev interaction model can guide further studies of the Nb 190 effect on HIV-1 Rev function and could serve as starting point for the rational development of smaller entities binding to the Nb 190 epitope, aimed at interfering with protein-protein interactions of the Rev N-terminal domain.