Project 6: Mothes/Blanchard Conformational trajectories of inhibitor-bound HIV-1 envelope Summary The design of effective antiviral therapies directed against HIV Env pursued by this program requires a fast method to determine the underlying molecular mechanism of HIV Env inhibition by small molecule inhibitors. Towards this end, we have established single-molecule Fluorescence Resonance Energy Transfer (smFRET) methods to visualize directly the structural dynamics of HIV Env in the context of the complete trimer on the surface of HIV virions. As a proof of concept we have successfully applied smFRET to the X4-tropic HIV-1 NL4-3- Our work reveals that the unliganded HIV Env is conformationally dynamic and intrinsically capable of sampling receptor CD4- and 17b-stabilized conformations. Importantly, the co-receptor binding site is more likely to be accessed from the CD4-induced state. Binding of CD4 lowers the energy of the CD4-stabilized conformation and prepares the HIV Env for co-receptor binding. These data explain how HIV Env is activated in a stepwise manner by CD4 and the co-receptor. Here, we will extend the application of smFRET to include physiologically relevant R5-tropic HIV-1 Env isolates. Dually modified HIV-1 Env variants will be used to determine the conformational trajectories of HIV Env induced by CD4 mimetics and antagonists. This will allow distinction between CD4 mimics such as NBD556 that induce CD4-like conformational changes and antagonists such as DMJ-l-228. smFRET imaging will also permit an understanding of conformational molecular events underlying HlV-1 inactivation either by prematurely activating Env, kinetic traps or allosterically diverting Env into off-pathways. As such, these smFRET technologies will provide a critical tool to determine the underlying molecular mechanism of HIV Env antagonism and inactivation developed by the Program Project Team and aid in a rational design of antiviral therapies that exploit the intrinsic vulnerabilities of HIV. smFRET technologies will accelerate pharmaceutical discovery by enabling screening for desired conformational effects that block, trap or inactivate HIV-1 Env.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Program Projects (P01)
Project #
2P01GM056550-17A1
Application #
8603518
Study Section
Special Emphasis Panel (ZRG1-AARR-E (43))
Project Start
Project End
Budget Start
2013-09-30
Budget End
2014-08-31
Support Year
17
Fiscal Year
2013
Total Cost
$328,072
Indirect Cost
$112,184
Name
Drexel University
Department
Type
DUNS #
002604817
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Castillo-Menendez, Luis R; Witt, Kristen; Espy, Nicole et al. (2018) Comparison of Uncleaved and Mature Human Immunodeficiency Virus Membrane Envelope Glycoprotein Trimers. J Virol 92:
Rashad, Adel A; Song, Li-Rui; Holmes, Andrew P et al. (2018) Bifunctional Chimera That Coordinately Targets Human Immunodeficiency Virus 1 Envelope gp120 and the Host-Cell CCR5 Coreceptor at the Virus-Cell Interface. J Med Chem 61:5020-5033
Moraca, Francesca; Rinaldo, David; Smith 3rd, Amos B et al. (2018) Specific Noncovalent Interactions Determine Optimal Structure of a Buried Ligand Moiety: QM/MM and Pure QM Modeling of Complexes of the Small-Molecule CD4 Mimetics and HIV-1 gp120. ChemMedChem 13:627-633
Castillo-Menendez, Luis R; Nguyen, Hanh T; Sodroski, Joseph (2018) Conformational Differences Between Functional Human Immunodeficiency Virus (HIV-1) Envelope Glycoprotein Trimers and Stabilized Soluble Trimers. J Virol :
Madani, Navid; Princiotto, Amy M; Mach, Linh et al. (2018) A CD4-mimetic compound enhances vaccine efficacy against stringent immunodeficiency virus challenge. Nat Commun 9:2363
Kisalu, Neville K; Idris, Azza H; Weidle, Connor et al. (2018) A human monoclonal antibody prevents malaria infection by targeting a new site of vulnerability on the parasite. Nat Med 24:408-416
Parajuli, Bibek; Acharya, Kriti; Bach, Harry C et al. (2018) Restricted HIV-1 Env glycan engagement by lectin-reengineered DAVEI protein chimera is sufficient for lytic inactivation of the virus. Biochem J 475:931-957
Ma, Xiaochu; Lu, Maolin; Gorman, Jason et al. (2018) HIV-1 Env trimer opens through an asymmetric intermediate in which individual protomers adopt distinct conformations. Elife 7:
Madani, Navid; Princiotto, Amy M; Zhao, Connie et al. (2017) Activation and Inactivation of Primary Human Immunodeficiency Virus Envelope Glycoprotein Trimers by CD4-Mimetic Compounds. J Virol 91:
Prévost, Jérémie; Zoubchenok, Daria; Richard, Jonathan et al. (2017) Influence of the Envelope gp120 Phe 43 Cavity on HIV-1 Sensitivity to Antibody-Dependent Cell-Mediated Cytotoxicity Responses. J Virol 91:

Showing the most recent 10 out of 146 publications