Functional and structural features of γ‐zeathionins, a new class of sodium channel blockers
- 4 December 1998
- journal article
- Published by Wiley in FEBS Letters
- Vol. 440 (3) , 302-306
- https://doi.org/10.1016/s0014-5793(98)01480-x
Abstract
γ1‐ and γ2‐zeathionins (γ1‐Z and γ2‐Z) are members of a family of small and basic peptides involved in plant protection. These plant defensins exhibit remarkable structural similarity to scorpion neurotoxins and insect defensins. In the present report, we used the whole‐cell patch clamp technique to investigate the inhibition of the sodium current (I Na) by γ1‐Z and γ2‐Z in the GH3 cell line. Both γ1‐Z and γ2‐Z rapidly and reversibly inhibited I Na without changing the kinetics or voltage dependence of activation or inactivation. To our knowledge, this is the first example of a plant protein that inhibits the sodium channel. From structural comparisons with the μ‐conotoxins, a family of peptides that block the sodium channel, we detected some similar features that could provide the basis of inhibition of sodium channels by γ‐zeathionins.Keywords
This publication has 34 references indexed in Scilit:
- Isolation and characterisation of plant defensins from seeds of Asteraceae, Fabaceae, Hippocastanaceae and SaxifragaceaeFEBS Letters, 1995
- CALCIUM CHANNEL DIVERSITY AND NEUROTRANSMITTER RELEASE: The ω-Conotoxins and ω-AgatoxinsAnnual Review of Biochemistry, 1994
- Solution structure of .gamma.1-H and .gamma.1-P thionins from barley and wheat endosperm determined by proton NMR: a structural motif common to toxic arthropod proteinsBiochemistry, 1993
- Action of derivatives of .mu.-conotoxin GIIIA on sodium channels. Single amino acid substitutions in the toxin separately affect association and dissociation ratesBiochemistry, 1992
- A new family of small (5 kDa) protein inhibitors of insect α‐amylases from seeds or sorghum (Sorghum bicolor (L) Moench) have sequence homologies with wheat γ‐purothioninsFEBS Letters, 1991
- Primary structure and inhibition of protein synthesis in eukaryotic cell‐free system of a novel thionin, γ‐hordothionin, from barley endospermEuropean Journal of Biochemistry, 1990
- γ‐Purothionins: amino acid sequence of two polypeptides of a new family of thionins from wheat endospermFEBS Letters, 1990
- Disulfide pairings in geographutoxin I, a peptide neurotoxin from Conus geographusFEBS Letters, 1990
- .mu.-Conotoxin GIIIA, a peptide ligand for muscle sodium channels: chemical synthesis, radiolabeling and receptor characterizationBiochemistry, 1989
- PEPTIDE TOXINS FROM VENOMOUS CONUS SNAILSAnnual Review of Biochemistry, 1988