Pompilidotoxins (PMTXs, α and β) are small peptides consisting of 13 amino acids purified from the venom of the solitary wasps Anoplius samariensis (α-PMTX) and Batozonellus maculifrons (β-PMTX). They are known to facilitate synaptic transmission in the lobster neuromuscular junction, and to slow sodium channel inactivation. By using β-PMTX, α-PMTX and four synthetic analogs with amino acid changes, we conducted a thorough study of the effects of PMTXs on sodium current inactivation in seven mammalian voltage-gated sodium channel (VGSC) isoforms and one insect VGSC (DmNa v1). By evaluating three components of which the inactivating current is composed (fast, slow and steady-state components), we could distinguish three distinct groups of PMTX effects. The first group concerned the insect and Nav1.6 channels, which showed a large increase in the steady-state current component without any increase in the slow component. Moreover, the dose-dependent increase in this steady-state component was correlated with the dose-dependent decrease in the fast component. A second group of effects concerned the Nav1.1, Nav1.2, Nav1.3 and Nav1.7 isoforms, which responded with a large increase in the slow component, and showed only a small steady-state component. As with the first group of effects, the slow component was dose-dependent and correlated with the decrease in the fast component. Finally, a third group of effects concerned Nav1.4 and Nav1.5, which did not show any change in the slow or steady-state component. These data shed light on the complex and intriguing behavior of VGSCs in response to PMTXs, helping us to better understand the molecular determinants explaining isoform-specific effects. © 2010 FEBS.
Schiavon, E., Stevens, M., Zaharenko, ., Konno K, Tytgat, J., & Wanke, E. (2010). Voltage-gated Sodium Channels Isoform-specific Effects of Pompilidotoxins. THE FEBS JOURNAL, 277(4), 918-930.
Citazione: | Schiavon, E., Stevens, M., Zaharenko, ., Konno K, Tytgat, J., & Wanke, E. (2010). Voltage-gated Sodium Channels Isoform-specific Effects of Pompilidotoxins. THE FEBS JOURNAL, 277(4), 918-930. |
Tipo: | Articolo in rivista - Articolo scientifico |
Carattere della pubblicazione: | Scientifica |
Titolo: | Voltage-gated Sodium Channels Isoform-specific Effects of Pompilidotoxins |
Autori: | Schiavon, E; Stevens, M; Zaharenko,, A; Konno K; Tytgat, J; Wanke, E |
Autori: | |
Data di pubblicazione: | feb-2010 |
Lingua: | English |
Rivista: | THE FEBS JOURNAL |
Digital Object Identifier (DOI): | http://dx.doi.org/10.1111/j.1742-4658.2009.07533.x |
Appare nelle tipologie: | 01 - Articolo su rivista |