7N6U

Structure of uncleaved HIV-1 JR-FL Env glycoprotein trimer in state U1 bound to small Molecule HIV-1 Entry Inhibitor BMS-378806

7N6U の概要

• エントリーDOI: 10.2210/pdb7n6u/pdb
• EMDBエントリー: 23860
• 分子名称: Envelope glycoprotein gp160, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, ... (8 entities in total)
• 機能のキーワード: hiv-1, envelope, virus, glycoprotein, viral protein
• 由来する生物種: Human immunodeficiency virus 1
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 319809.52

構造登録者

Zhang, S.,Wang, K.,Mao, Y. (登録日: 2021-06-09, 公開日: 2021-09-22, 最終更新日: 2021-12-08)

主引用文献

Zhang, S.,Wang, K.,Wang, W.L.,Nguyen, H.T.,Chen, S.,Lu, M.,Go, E.P.,Ding, H.,Steinbock, R.T.,Desaire, H.,Kappes, J.C.,Sodroski, J.,Mao, Y.
Asymmetric Structures and Conformational Plasticity of the Uncleaved Full-Length Human Immunodeficiency Virus Envelope Glycoprotein Trimer.
J.Virol., 95:e0052921-e0052921, 2021

PubMed Abstract: The functional human immunodeficiency virus (HIV-1) envelope glycoprotein (Env) trimer [(gp120/gp41)] is produced by cleavage of a conformationally flexible gp160 precursor. gp160 cleavage or the binding of BMS-806, an entry inhibitor, stabilizes the pretriggered, "closed" (state 1) conformation recognized by rarely elicited broadly neutralizing antibodies. Poorly neutralizing antibodies (pNAbs) elicited at high titers during natural infection recognize more "open" Env conformations (states 2 and 3) induced by binding the receptor, CD4. We found that BMS-806 treatment and cross-linking decreased the exposure of pNAb epitopes on cell surface gp160; however, after detergent solubilization, cross-linked and BMS-806-treated gp160 sampled non-state-1 conformations that could be recognized by pNAbs. Cryo-electron microscopy of the purified BMS-806-bound gp160 revealed two hitherto unknown asymmetric trimer conformations, providing insights into the allosteric coupling between trimer opening and structural variation in the gp41 HR1 region. The individual protomer structures in the asymmetric gp160 trimers resemble those of other genetically modified or antibody-bound cleaved HIV-1 Env trimers, which have been suggested to assume state-2-like conformations. Asymmetry of the uncleaved Env potentially exposes surfaces of the trimer to pNAbs. To evaluate the effect of stabilizing a state-1-like conformation of the membrane Env precursor, we treated cells expressing wild-type HIV-1 Env with BMS-806. BMS-806 treatment decreased both gp160 cleavage and the addition of complex glycans, implying that gp160 conformational flexibility contributes to the efficiency of these processes. Selective pressure to maintain flexibility in the precursor of functional Env allows the uncleaved Env to sample asymmetric conformations that potentially skew host antibody responses toward pNAbs. The envelope glycoprotein (Env) trimers on the surface of human immunodeficiency virus (HIV-1) mediate the entry of the virus into host cells and serve as targets for neutralizing antibodies. The functional Env trimer is produced by cleavage of the gp160 precursor in the infected cell. We found that the HIV-1 Env precursor is highly plastic, allowing it to assume different asymmetric shapes. This conformational plasticity is potentially important for Env cleavage and proper modification by sugars. Having a flexible, asymmetric Env precursor that can misdirect host antibody responses without compromising virus infectivity would be an advantage for a persistent virus like HIV-1.

PubMed: 34549974
DOI: 10.1128/JVI.00529-21

実験手法

ELECTRON MICROSCOPY (4.1 Å)