1G2G

MINIMAL CONFORMATION OF THE ALPHA-CONOTOXIN IMI FOR THE ALPHA7 NEURONAL NICOTINIC ACETYLCHOLINE RECEPTOR RECOGNITION


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 60 
  • Conformers Submitted: 30 
  • Selection Criteria: structures with the least restraint violations,structures with the lowest energy 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Minimal conformation of the alpha-conotoxin ImI for the alpha7 neuronal nicotinic acetylcholine receptor recognition: correlated CD, NMR and binding studies.

Lamthanh, H.Jegou-Matheron, C.Servent, D.Menez, A.Lancelin, J.M.

(1999) FEBS Lett 454: 293-298

  • DOI: 10.1016/s0014-5793(99)00831-5
  • Primary Citation of Related Structures:  
    1G2G

  • PubMed Abstract: 
  • The alpha-ImI conotoxin, a selective potent inhibitor of the mammalian neuronal alpha7 nicotinic acetylcholine receptor (n-AchR), was shown by point mutation or by L-alanine scanning to display two regions essential for bioactivity: the active site Asp5-Pro6-Arg7 in the first loop and Trp10 in the second loop ...

    The alpha-ImI conotoxin, a selective potent inhibitor of the mammalian neuronal alpha7 nicotinic acetylcholine receptor (n-AchR), was shown by point mutation or by L-alanine scanning to display two regions essential for bioactivity: the active site Asp5-Pro6-Arg7 in the first loop and Trp10 in the second loop. The deletion of the Cys3,Cys12 disulfide bond in the alpha-ImI scaffold, e.g. peptide II, had no effect on its binding affinity. CD spectra, NMR studies and structure calculations were carried out on the wild type alpha-ImI, the weakest analog (R7A) and peptide II (equipotent to alpha-ImI) in order to point out the conformational differences between these compounds. Then, an attempt to correlate the conformational data and the affinity results was proposed. CD and NMR data were identical for the R7A analog and alpha-ImI, revealing the crucial functional role of the Arg7 side chain. On the other hand, the scaffold of the first loop in peptide II was shown by NMR to represent the minimal conformation for the optimal interaction of the toxin with the neuronal alpha7 n-AchR. Last, the beta-turn forming property of the 6th residue (Pro) in the active site of the alpha-ImI can be correlated with its affinity.


    Related Citations: 
    • A Nicotinic Acetylcholine Receptor Ligand of Unique Specificity, alpha-Conotoxin ImI
      McIntosh, J.M., Yoshikami, D., Mahe, E., Nielsen, D.B., Rivier, J.E., Gray, W.R., Olivera, B.M.
      (1994) J Biol Chem 269: 16733
    • Functional Determinants by which Snake and Cone Snail Toxins Block the alpha 7 Neuronal Nicotinic Acetylcholine Receptors
      Servent, D., Lamthanh, H., Antil, S., Bertrand, D., Corringer, P.J., Changeux, J.P., Menez, A.
      (1998) J Physiol (Paris) 92: 107
    • Identification of Residues in the Neuronal alpha7 Acetylcholine Receptor that Confer Selectivity for Conotoxin ImI
      Quiram, P.A., Sine, S.M.
      (1998) J Biol Chem 273: 11001
    • NMR Spatial Structure of alpha-Conotoxin ImI Reveals a Common Scaffold in Snail and Snake Toxins Recognizing Neuronal Nicotinic Acetylcholine Receptors
      Maslennikov, I.V., Shenkarev, Z.O., Zhmak, M.N., Ivanov, V.T., Methfessel, C., Tsetlin, V.I., Arseniev, A.S.
      (1999) FEBS Lett 444: 275
    • NMR Solution Structure of alpha-Conotoxin ImI and Comparison to other Conotoxins Specific for Neuronal Nicotinic Acetylcholine Receptors
      Rogers, J.P., Luginbuhl, P., Shen, G.S., McCabe, R.T., Stevens, R.C., Wemmer, D.E.
      (1999) Biochemistry 38: 3874

    Organizational Affiliation

    CEA, Département d'Ingénierie et d'Etudes des Protéines, Gif sur Yvette, France. lamthanh@dsvidf.cea.fr



Macromolecules
  • Find similar proteins by:  Sequence   |   Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
ALPHA-CONOTOXIN IMIA13N/AMutation(s): 0 
UniProt
Find proteins for P50983 (Conus imperialis)
Explore P50983 
Go to UniProtKB:  P50983
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 60 
  • Conformers Submitted: 30 
  • Selection Criteria: structures with the least restraint violations,structures with the lowest energy 
  • OLDERADO: 1G2G Olderado

Structure Validation

View Full Validation Report




Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2000-11-08
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance