5AIN

Varenicline Interactions at the 5HT3 Receptor Ligand Binding Site are Revealed by 5HTBP


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.162 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Varenicline Interactions at the 5-Ht3 Receptor Ligand Binding Site are Revealed by 5-Htbp.

Price, K.L.Lillestol, R.K.Ulens, C.Lummis, S.C.R.

(2015) Acs Chem Neurosci 6: 1151

  • DOI: 10.1021/cn500369h

  • PubMed Abstract: 
  • Cys-loop receptors are the site of action of many therapeutic drugs. One of these is the smoking cessation agent varenicline, which has its major therapeutic effects at nicotinic acetylcholine (nACh) receptors but also acts at 5-HT3 receptors. Here, ...

    Cys-loop receptors are the site of action of many therapeutic drugs. One of these is the smoking cessation agent varenicline, which has its major therapeutic effects at nicotinic acetylcholine (nACh) receptors but also acts at 5-HT3 receptors. Here, we report the X-ray crystal structure of the 5-HT binding protein (5-HTBP) in complex with varenicline, and test the predicted interactions by probing the potency of varenicline in a range of mutant 5-HT3 receptors expressed in HEK293 cells and Xenopus oocytes. The structure reveals a range of interactions between varenicline and 5-HTBP. We identified residues within 5 √Ö of varenicline and substituted the equivalent residues in the 5-HT3 receptor with Ala or a residue with similar chemical properties. Functional characterization of these mutant 5-HT3 receptors, using a fluorescent membrane potential dye in HEK cells and voltage clamp in oocytes, supports interactions between varenicline and the receptor that are similar to those in 5-HTBP. The structure also revealed C-loop closure that was less than in the 5-HT-bound 5-HTBP, and hydrogen bonding between varenicline and the complementary face of the binding pocket via a water molecule, which are characteristics consistent with partial agonist behavior of varenicline in the 5-HT3 receptor. Together, these data reveal detailed insights into the molecular interaction of varenicline in the 5-HT3 receptor.


    Organizational Affiliation

    †Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, United Kingdom.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
SOLUBLE ACETYLCHOLINE RECEPTOR
A, B, C, D, E
212Aplysia californicaMutation(s): 0 
Find proteins for Q8WSF8 (Aplysia californica)
Go to UniProtKB:  Q8WSF8
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
QMR
Query on QMR

Download SDF File 
Download CCD File 
A, B, C, D, E
VARENICLINE
C13 H13 N3
JQSHBVHOMNKWFT-DTORHVGOSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.3 Å
  • R-Value Free: 0.224 
  • R-Value Work: 0.162 
  • Space Group: P 41 21 2
Unit Cell:
Length (Å)Angle (°)
a = 72.794α = 90.00
b = 72.794β = 90.00
c = 479.221γ = 90.00
Software Package:
Software NamePurpose
SCALAdata scaling
PHENIXrefinement
XDSdata reduction
MOLREPphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2015-03-25
    Type: Initial release
  • Version 1.1: 2016-03-30
    Type: Database references