Three-dimensional Modelling of the Voltage-gated Sodium Ion Channel from Anopheles gambiae Reveals Spatial Clustering of Evolutionarily Conserved Acidic Residues at the Extracellular Sites

Title:Three-dimensional Modelling of the Voltage-gated Sodium Ion Channel from Anopheles gambiae Reveals Spatial Clustering of Evolutionarily Conserved Acidic Residues at the Extracellular Sites

Volume: 15 Issue: 8

Author(s): Rithvik S. Vinekar and Ramanathan Sowdhamini*

Affiliation:

• National Centre for Biological Sciences (TIFR), GKVK Campus, Bellary Road, Bangalore,India

Keywords: Eukaryotic voltage gated sodium channel, homology model, pore blocker, toxin, extracellular interface, transmembrane, anopheles.

Abstract: Background: The eukaryotic voltage-gated sodium channel(e-Nav) is a large asymmetric transmembrane protein with important functions concerning neurological function. No structure has been resolved at high resolution for this protein.

Methods: A homology model of the transmembrane and extracellular regions of an Anopheles gambiae para-like channel with emphasis on the pore entrance has been constructed, based upon the templates provided by a prokaryotic sodium channel and a potassium two-pore channel. The latter provides a template for the extracellular regions, which are located above the entrance to the pore, which is likely to open at a side of a dome formed by these loops.

Results: A model created with this arrangement shows a structure similar to low-resolution cryoelectron microscope images of a related structure. The pore entrance also shows favorable electrostatic interface.

Conclusion: Residues responsible for the negative charge around the pore have been traced in phylogeny to highlight their importance. This model is intended for the study of pore-blocking toxins.

Cite this article as:

Vinekar S. Rithvik and Sowdhamini Ramanathan*, Three-dimensional Modelling of the Voltage-gated Sodium Ion Channel from Anopheles gambiae Reveals Spatial Clustering of Evolutionarily Conserved Acidic Residues at the Extracellular Sites, Current Neuropharmacology 2017; 15 (8) . https://dx.doi.org/10.2174/1567201814666161205131213