Does interaction between anti-insect scorpion toxin LqhαIT and cockroach sodium channel is voltage dependent?

• Autorzy: Dabrowski M. , Stankiewicz M. , Nowak W.
• Języki publikacji: EN

Abstrakty

EN

Scorpion toxins (α toxins) binding to receptor site 3 of sodium channel (Nav) inhibit the inactivation of the activated channel. Binding of α toxins selective to mammals is voltage dependent. Interaction of insect selective α toxin (LqhαIT) with insect Na channel is characterized as voltage independent. Results of our electrophysiological experiments performed on cockroach axonal membrane are quite contradictory. Evoked plateau action potentials, recorded after LqhαIT application are shortened when axon is stimulated with high frequency. Such effect can be partially abolished by higher toxin concentration. In voltage clamp, when depolarizing pulses are applied with high frequency the decrease of size of toxin induced late sodium current is observed. To study molecular mechanisms of these phenomena molecular dynamics methods was used. Calculation was performed for complex system – LqhαIT with domain IV of Nav – with using CHARMM force field. Simulations were performed in present and absent of an electric field. That in silico research shows some correlation between the number of hydrogen bonds linking site 3 of domain IV and LqhαIT and deviations of atoms of segment S4. Studies supported by MNiSW (Poland)-grant N N303 320637; M. Dąbrowski is a beneficiary of PhD grant: Project No POKL.0401.01-00-081/10.

• Wydawca: -
• Czasopismo: Acta Neurobiologiae Experimentalis
• Rocznik: 2013
• Tom: 73
• Numer: Suppl.1
• Opis fizyczny: p.24-25

Twórcy

autor

Dabrowski M.

• Institute of Physics,Nicolaus Copernicus University, Torun, Poland
• Faculty of Biology and Environment Protection, Nicolaus Copernicus University, Torun, Poland

autor

Stankiewicz M.

• Faculty of Biology and Environment Protection, Nicolaus Copernicus University, Torun, Poland

autor

Nowak W.

• Institute of Physics,Nicolaus Copernicus University, Torun, Poland