Hongotoxin

Hongotoxin (HgTX) is an ion channel toxin, which blocks Shaker-type (Kv1) K+ channels. The toxin is derived from the venom of Centruroides limbatus, a Central American scorpion found meanly in Costa Rica, Honduras and Panama.

Chemistry
Hongotoxin belongs to the short scorpion toxin superfamily. Potassium channel inhibitor family. Alpha-KTx 2 subfamily.

There are five subtypes known of the hongotoxin peptide. HgTX1 is 39 amino acids long and shows an overall amino acid sequence homology of 89% to margatoxin (MgTX).

Target
Hongotoxin (HgTX) targets are Shaker-type (Kv1) K+ channels.

HgTX1 shows high affinity with Kv1.1, Kv1.2, Kv1.3 voltage-gated potassium channels, but much lower affinity with Kv1.6 (see table 1 and 2 ).

HgTX2, HgTX3, HgTX4 and HgTX5 are potent selective inhibitors of Kv1 voltage-gated potassium channels (By similarity).

ND, not determined. All measurements in pM All measurements in pM

Mode of action
The mode of action is not yet known.