Fluorescent Protein-Scorpion Toxin Chimera Is a Convenient Molecular Tool for Studies of Potassium Channels

Sci Rep. 2016 Sep 21;6:33314. doi: 10.1038/srep33314.

Abstract

Ion channels play a central role in a host of physiological and pathological processes and are the second largest target for existing drugs. There is an increasing need for reliable tools to detect and visualize particular ion channels, but existing solutions suffer from a number of limitations such as high price, poor specificity, and complicated protocols. As an alternative, we produced recombinant chimeric constructs (FP-Tx) consisting of fluorescent proteins (FP) fused with potassium channel toxins from scorpion venom (Tx). In particular, we used two FP, eGFP and TagRFP, and two Tx, OSK1 and AgTx2, to create eGFP-OSK1 and RFP-AgTx2. We show that these chimeras largely retain the high affinity of natural toxins and display selectivity to particular ion channel subtypes. FP-Tx are displaced by other potassium channel blockers and can be used as an imaging tool in ion channel ligand screening setups. We believe FP-Tx chimeras represent a new efficient molecular tool for neurobiology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cells, Cultured
  • Drug Evaluation, Preclinical / methods
  • Escherichia coli
  • Green Fluorescent Proteins / pharmacology
  • Inhibitory Concentration 50
  • Membrane Potentials / drug effects
  • Oocytes
  • Potassium Channel Blockers / pharmacology*
  • Potassium Channels, Voltage-Gated / antagonists & inhibitors*
  • Potassium Channels, Voltage-Gated / metabolism
  • Recombinant Fusion Proteins / pharmacology
  • Scorpion Venoms / pharmacology*
  • Xenopus laevis

Substances

  • Potassium Channel Blockers
  • Potassium Channels, Voltage-Gated
  • Recombinant Fusion Proteins
  • Scorpion Venoms
  • enhanced green fluorescent protein
  • Green Fluorescent Proteins