2MPQ

Solution structure of the sodium channel toxin Hd1a


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 20 
  • Selection Criteria: Best MobProbity score 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Seven novel modulators of the analgesic target NaV 1.7 uncovered using a high-throughput venom-based discovery approach.

Klint, J.K.Smith, J.J.Vetter, I.Rupasinghe, D.B.Er, S.Y.Senff, S.Herzig, V.Mobli, M.Lewis, R.J.Bosmans, F.King, G.F.

(2015) Br J Pharmacol 172: 2445-2458

  • DOI: https://doi.org/10.1111/bph.13081
  • Primary Citation of Related Structures:  
    2MPQ

  • PubMed Abstract: 

    Chronic pain is a serious worldwide health issue, with current analgesics having limited efficacy and dose-limiting side effects. Humans with loss-of-function mutations in the voltage-gated sodium channel NaV 1.7 (hNaV 1.7) are indifferent to pain, making hNaV 1.7 a promising target for analgesic development. Since spider venoms are replete with NaV channel modulators, we examined their potential as a source of hNaV 1.7 inhibitors. We developed a high-throughput fluorescent-based assay to screen spider venoms against hNaV 1.7 and isolate 'hit' peptides. To examine the binding site of these peptides, we constructed a panel of chimeric channels in which the S3b-S4 paddle motif from each voltage sensor domain of hNaV 1.7 was transplanted into the homotetrameric KV 2.1 channel. We screened 205 spider venoms and found that 40% contain at least one inhibitor of hNaV 1.7. By deconvoluting 'hit' venoms, we discovered seven novel members of the NaSpTx family 1. One of these peptides, Hd1a (peptide μ-TRTX-Hd1a from venom of the spider Haplopelma doriae), inhibited hNaV 1.7 with a high level of selectivity over all other subtypes, except hNaV 1.1. We showed that Hd1a is a gating modifier that inhibits hNaV 1.7 by interacting with the S3b-S4 paddle motif in channel domain II. The structure of Hd1a, determined using heteronuclear NMR, contains an inhibitor cystine knot motif that is likely to confer high levels of chemical, thermal and biological stability. Our data indicate that spider venoms are a rich natural source of hNaV 1.7 inhibitors that might be useful leads for the development of novel analgesics.


  • Organizational Affiliation

    Centre for Pain Research, Institute for Molecular Bioscience, St. Lucia, Qld, Australia.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Hd1a36HaplopelmaMutation(s): 0 
UniProt
Find proteins for A0A0J9X1W9 (Cyriopagopus doriae)
Explore A0A0J9X1W9 
Go to UniProtKB:  A0A0J9X1W9
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupA0A0J9X1W9
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 200 
  • Conformers Submitted: 20 
  • Selection Criteria: Best MobProbity score 

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2015-03-25
    Type: Initial release
  • Version 1.1: 2015-05-06
    Changes: Database references
  • Version 1.2: 2023-06-14
    Changes: Data collection, Database references, Other