1V91

Solution structure of insectidal toxin delta-paluIT2-NH2


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Submitted: 20 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Solution structure of two insect-specific spider toxins and their pharmacological interaction with the insect voltage-gated Na(+) channel

Ferrat, G.Bosmans, F.Tytgat, J.Pimentel, C.Chagot, B.Gilles, N.Nakajima, T.Darbon, H.Corzo, G.

(2005) Proteins 59: 368-379

  • DOI: 10.1002/prot.20424
  • Primary Citation of Related Structures:  
    1V91, 1V90

  • PubMed Abstract: 
  • Delta-paluIT1 and delta-paluIT2 are toxins purified from the venom of the spider Paracoelotes luctuosus. Similar in sequence to mu-agatoxins from Agelenopsis aperta, their pharmacological target is the voltage-gated insect sodium channel, of which th ...

    Delta-paluIT1 and delta-paluIT2 are toxins purified from the venom of the spider Paracoelotes luctuosus. Similar in sequence to mu-agatoxins from Agelenopsis aperta, their pharmacological target is the voltage-gated insect sodium channel, of which they alter the inactivation properties in a way similar to alpha-scorpion toxins, but they bind on site 4 in a way similar to beta-scorpion toxins. We determined the solution structure of the two toxins by use of two-dimensional nuclear magnetic resonance (NMR) techniques followed by distance geometry and molecular dynamics. The structures of delta-paluIT1 and delta-paluIT2 belong to the inhibitory cystine knot structural family, i.e. a compact disulfide-bonded core from which four loops emerge. Delta-paluIT1 and delta-paluIT2 contain respectively two- and three-stranded anti-parallel beta-sheets as unique secondary structure. We compare the structure and the electrostatic anisotropy of those peptides to other sodium and calcium channel toxins, analyze the topological juxtaposition of key functional residues, and conclude that the recognition of insect voltage-gated sodium channels by these toxins involves the beta-sheet, in addition to loops I and IV. Besides the position of culprit residues on the molecular surface, difference in dipolar moment orientation is another determinant of receptor binding and biological activity differences. We also demonstrate by electrophysiological experiments on the cloned insect voltage-gated sodium channel, para, heterologuously co-expressed with the tipE subunit in Xenopus laevis oocytes, that delta-paluIT1 and delta-paluIT2 procure an increase of Na+ current. delta-PaluIT1-OH seems to have less effect when the same concentrations are used.


    Organizational Affiliation

    Suntory Institute for Bioorganic Research, Mishima-Gun, Shimamoto-Cho, Osaka, Japan.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Delta-palutoxin IT2A38Pireneitega luctuosaMutation(s): 0 
Find proteins for P83257 (Pireneitega luctuosa)
Explore P83257 
Go to UniProtKB:  P83257
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Submitted: 20 
  • OLDERADO: 1V91 Olderado

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2005-03-29
    Type: Initial release
  • Version 1.1: 2008-04-27
    Changes: Version format compliance
  • Version 1.2: 2011-07-13
    Changes: Version format compliance