1RYV

Three dimensional solution structure of the K27A MUTANT of sodium channels inhibitor HAINANTOXIN-IV BY 2D 1H-NMR


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure--activity relationships of hainantoxin-IV and structure determination of active and inactive sodium channel blockers

Li, D.Xiao, Y.Xu, X.Xiong, X.Lu, S.Liu, Z.Zhu, Q.Wang, M.Gu, X.Liang, S.

(2004) J.Biol.Chem. 279: 37734-37740

  • DOI: 10.1074/jbc.M405765200
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Hainantoxin-IV (HNTX-IV) can specifically inhibit the neuronal tetrodotoxin-sensitive sodium channels and defines a new class of depressant spider toxin. The sequence of native HNTX-IV is ECLGFGKGCNPSNDQCCKSSNLVCSRKHRWCKYEI-NH(2). In the present stud ...

    Hainantoxin-IV (HNTX-IV) can specifically inhibit the neuronal tetrodotoxin-sensitive sodium channels and defines a new class of depressant spider toxin. The sequence of native HNTX-IV is ECLGFGKGCNPSNDQCCKSSNLVCSRKHRWCKYEI-NH(2). In the present study, to obtain further insight into the primary and tertiary structural requirements of neuronal sodium channel blockers, we determined the solution structure of HNTX-IV as a typical inhibitor cystine knot motif and synthesized four mutants designed based on the predicted sites followed by structural elucidation of two inactive mutants. Pharmacological studies indicated that the S12A and R26A mutants had activities near that of native HNTX-IV, while K27A and R29A demonstrated activities reduced by 2 orders of magnitude. (1)H MR analysis showed the similar molecular conformations for native HNTX-IV and four synthetic mutants. Furthermore, in the determined structures of K27A and R29A, the side chains of residues 27 and 29 were located in the identical spatial position to those of native HNTX-IV. These results suggested that residues Ser(12), Arg(26), Lys(27), and Arg(29) were not responsible for stabilizing the distinct conformation of HNTX-IV, but Lys(27) and Arg(29) were critical for the bioactivities. The potency reductions produced by Ala substitutions were primarily due to the direct interaction of the essential residues Lys(27) and Arg(29) with sodium channels rather than to a conformational change. After comparison of these structures and activities with correlated toxins, we hypothesized that residues Lys(27), Arg(29), His(28), Lys(32), Phe(5), and Trp(30) clustered on one face of HNTX-IV were responsible for ligand binding.


    Related Citations: 
    • Synthesis and Oxidative Refolding of Hainantoxin-Iv
      Liu, Z.H.,Chen, P.,Liang, S.P.
      (2002) Acta Biochim.Biophys.Sinica 34: 516
    • Isolation and characterization of hainantoxin-IV, a novel antagonist of tetrodotoxin-sensitive sodium channels from the Chinese bird spider Selenocosmia hainana
      Liu, Z.,Dai, J.,Chen, Z.,Hu, W.,Xiao, Y.,Liang, S.
      (2003) Cell.Mol.Life Sci. 60: 972


    Organizational Affiliation

    College of Life Sciences, Peking University, Beijing 100871, China.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Hainantoxin-IV
A
36Cyriopagopus hainanusMutation(s): 1 
Find proteins for D2Y232 (Cyriopagopus hainanus)
Go to UniProtKB:  D2Y232
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
NH2
Query on NH2
A
NON-POLYMERH2 N

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Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 50 
  • Conformers Submitted: 20 
  • Selection Criteria: structures with the lowest energy 
  • Olderado: 1RYV Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2004-01-13
    Type: Initial release
  • Version 1.1: 2008-04-29
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance