An inhibitor of the Kv2.1 potassium channel isolated from the venom of a Chilean tarantula

@article{Swartz1995AnIO,
  title={An inhibitor of the Kv2.1 potassium channel isolated from the venom of a Chilean tarantula},
  author={Kenton Jon Swartz and Roderick MacKinnon},
  journal={Neuron},
  year={1995},
  volume={15},
  pages={941-949}
}
The Kv2.1 voltage-activated K+ channel, a Shab-related K+ channel isolated from rat brain, is insensitive to previously identified peptide inhibitors. We have isolated two peptides from the venom of a Chilean tarantula, G. spatulata, that inhibit the Kv2.1 K+ channel. The two peptides, hanatoxin1 (HaTx1) and hanatoxin2 (HaTx2) are unrelated in primary sequence to other K+ channel inhibitors. The activity of HaTx was verified by synthesizing it in a bacterial expression system. The concentration… 

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