2JUT

alpha RgIA, a Novel Conotoxin that Blocks the alpha9-alpha10 nAChR


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Alpha-RgIA, a novel conotoxin that blocks the alpha9alpha10 nAChR: structure and identification of key receptor-binding residues.

Ellison, M.Feng, Z.P.Park, A.J.Zhang, X.Olivera, B.M.McIntosh, J.M.Norton, R.S.

(2008) J.Mol.Biol. 377: 1216-1227

  • DOI: 10.1016/j.jmb.2008.01.082
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Alpha-conotoxins are small disulfide-constrained peptides from cone snails that act as antagonists at specific subtypes of nicotinic acetylcholine receptors (nAChRs). The 13-residue peptide alpha-conotoxin RgIA (alpha-RgIA) is a member of the alpha-4 ...

    Alpha-conotoxins are small disulfide-constrained peptides from cone snails that act as antagonists at specific subtypes of nicotinic acetylcholine receptors (nAChRs). The 13-residue peptide alpha-conotoxin RgIA (alpha-RgIA) is a member of the alpha-4,3 family of alpha-conotoxins and selectively blocks the alpha9alpha10 nAChR subtype, in contrast to another well-characterized member of this family, alpha-conotoxin ImI (alpha-ImI), which is a potent inhibitor of the alpha7 and alpha3beta2 nAChR subtypes. In this study, we have altered side chains in both the four-residue and the three-residue loops of alpha-RgIA, and have modified its C-terminus. The effects of these changes on activity against alpha9alpha10 and alpha7 nAChRs were measured; the solution structures of alpha-RgIA and its Y10W, D5E, and P6V analogues were determined from NMR data; and resonance assignments were made for alpha-RgIA [R9A]. The structures for alpha-RgIA and its three analogues were well defined, except at the chain termini. Comparison of these structures with reported structures of alpha-ImI reveals a common two-loop backbone architecture within the alpha-4,3 family, but with variations in side-chain solvent accessibility and orientation. Asp5, Pro6, and Arg7 in loop 1 are critical for blockade of both the alpha9alpha10 and the alpha7 subtypes. In loop 2, alpha-RgIA [Y10W] had activity near that of wild-type alpha-RgIA, with high potency for alpha9alpha10 and low potency for alpha7, and had a structure similar to that of wild type. By contrast, Arg9 in loop 2 is critical for specific binding to the alpha9alpha10 subtype, probably because it is larger and more solvent accessible than Ala9 in alpha-ImI. Our findings contribute to a better understanding of the molecular basis for antagonism of the alpha9alpha10 nAChR subtype, which is a target for the development of analgesics for the treatment of chronic neuropathic pain.


    Organizational Affiliation

    Department of Biology, University of Utah, Salt Lake City, UT 84112, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Alpha-conotoxin RgIA
A
13Conus regiusMutation(s): 0 
Find proteins for P0C1D0 (Conus regius)
Go to UniProtKB:  P0C1D0
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 100 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 
  • Olderado: 2JUT Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

  • Deposited Date: 2007-09-02 
  • Released Date: 2011-05-25 
  • Deposition Author(s): Feng, Z., Ellison, M.

Revision History 

  • Version 1.0: 2011-05-25
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Version format compliance