2M6X

Structure of the p7 channel of Hepatitis C virus, genotype 5a


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 60 
  • Conformers Submitted: 15 
  • Selection Criteria: structures with the least restraint violations 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Unusual architecture of the p7 channel from hepatitis C virus

OuYang, B.Xie, S.Berardi, M.J.Zhao, X.Dev, J.Yu, W.Sun, B.Chou, J.J.

(2013) Nature 498: 521-525

  • DOI: 10.1038/nature12283

  • PubMed Abstract: 
  • The hepatitis C virus (HCV) has developed a small membrane protein, p7, which remarkably can self-assemble into a large channel complex that selectively conducts cations. We wanted to examine the structural solution that the viroporin adopts in order ...

    The hepatitis C virus (HCV) has developed a small membrane protein, p7, which remarkably can self-assemble into a large channel complex that selectively conducts cations. We wanted to examine the structural solution that the viroporin adopts in order to achieve selective cation conduction, because p7 has no homology with any of the known prokaryotic or eukaryotic channel proteins. The activity of p7 can be inhibited by amantadine and rimantadine, which are potent blockers of the influenza M2 channel and licensed drugs against influenza infections. The adamantane derivatives have been used in HCV clinical trials, but large variation in drug efficacy among the various HCV genotypes has been difficult to explain without detailed molecular structures. Here we determine the structures of this HCV viroporin as well as its drug-binding site using the latest nuclear magnetic resonance (NMR) technologies. The structure exhibits an unusual mode of hexameric assembly, where the individual p7 monomers, i, not only interact with their immediate neighbours, but also reach farther to associate with the i+2 and i+3 monomers, forming a sophisticated, funnel-like architecture. The structure also points to a mechanism of cation selection: an asparagine/histidine ring that constricts the narrow end of the funnel serves as a broad cation selectivity filter, whereas an arginine/lysine ring that defines the wide end of the funnel may selectively allow cation diffusion into the channel. Our functional investigation using whole-cell channel recording shows that these residues are critical for channel activity. NMR measurements of the channel-drug complex revealed six equivalent hydrophobic pockets between the peripheral and pore-forming helices to which amantadine or rimantadine binds, and compound binding specifically to this position may allosterically inhibit cation conduction by preventing the channel from opening. Our data provide a molecular explanation for p7-mediated cation conductance and its inhibition by adamantane derivatives.


    Organizational Affiliation

    Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
p7
A, B, C, D, E, F
63Hepatitis C virus genotype 5aMutation(s): 5 
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Channels: Other Ion Channels
Protein: 
p7 hexamer channel
Find proteins for O39928 (Hepatitis C virus genotype 5a)
Go to UniProtKB:  O39928
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 60 
  • Conformers Submitted: 15 
  • Selection Criteria: structures with the least restraint violations 

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2013-04-12 
  • Released Date: 2013-06-12 
  • Deposition Author(s): OuYang, B., Chou, J.J.

Revision History 

  • Version 1.0: 2013-06-12
    Type: Initial release
  • Version 1.1: 2014-01-29
    Type: Database references