Unique mechanism of the interaction between honey bee toxin TPNQ and rKir1.1 potassium channel explored by computational simulations: insights into the relative insensitivity of channel towards animal toxins.

ABSTRACT:

Background

The 21-residue compact tertiapin-Q (TPNQ) toxin, a derivative of honey bee toxin tertiapin (TPN), is a potent blocker of inward-rectifier K(+) channel subtype, rat Kir1.1 (rKir1.1) channel, and their interaction mechanism remains unclear.

Principal findings

Based on the flexible feature of potassium channel turrets, a good starting rKir1.1 channel structure was modeled for the accessibility of rKir1.1 channel turrets to TPNQ toxin. In combination with experimental alanine scanning mutagenesis data, computational approaches were further used to obtain a reasonable TPNQ toxin-rKir1.1 channel complex structure, which was completely different from the known binding modes between animal toxins and potassium channels. TPNQ toxin mainly adopted its helical domain as the

SUBMITTER: Hu J 

PROVIDER: S-EPMC3707903 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature