Pompilidotoxins (PMTXs, alpha and beta) are small peptides consisting of 13 amino acids purified from the venom of the solitary wasps Anoplius samariensis (alpha-PMTX) and Batozonellus maculifrons (beta-PMTX). They are known to facilitate synaptic transmission in the lobster neuromuscular junction, and to slow sodium channel inactivation. By using beta-PMTX, alpha-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(v)1). 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 Na(v)1.6 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 Na(v)1.1, Na(v)1.2, Na(v)1.3 and Na(v)1.7 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 Na(v)1.4 and Na(v)1.5, 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.
Schiavon, E., Stevens, M., Zaharenko, A., Konno, K., Tytgat, J., & Wanke, E. (2010). Voltage-gated Sodium Channels Isoform-specific Effects of Pompilidotoxins. THE FEBS JOURNAL, 277(4), 918-930 [10.1111/j.1742-4658.2009.07533.x].
|Citazione:||Schiavon, E., Stevens, M., Zaharenko, A., Konno, K., Tytgat, J., & Wanke, E. (2010). Voltage-gated Sodium Channels Isoform-specific Effects of Pompilidotoxins. THE FEBS JOURNAL, 277(4), 918-930 [10.1111/j.1742-4658.2009.07533.x].|
|Tipo:||Articolo in rivista - Articolo scientifico|
|Carattere della pubblicazione:||Scientifica|
|Presenza di un coautore afferente ad Istituzioni straniere:||Si|
|Titolo:||Voltage-gated Sodium Channels Isoform-specific Effects of Pompilidotoxins|
|Autori:||Schiavon, E; Stevens, M; Zaharenko, A; Konno, K; Tytgat, J; Wanke, E|
|Data di pubblicazione:||2010|
|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|