Английская Википедия:Hongotoxin

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Hongotoxin (HgTX) is an ion channel toxin, which blocks Shaker-type (Kv1) K+ channels. The toxin is derived from the venom of Centruroides limbatus,[1] a Central American scorpion found meanly in Costa Rica, Honduras and Panama.[2]

Chemistry

Hongotoxin belongs to the short scorpion toxin superfamily. Potassium channel inhibitor family. Alpha-KTx 2 subfamily.[1]

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).[1]

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[1]).

HgTX2,[3] HgTX3,[4] HgTX4[5] and HgTX5[6] are potent selective inhibitors of Kv1 voltage-gated potassium channels (By similarity).

table 1 IC50
Kv1.1 Kv1.2 Kv1.3 Kv1.6
HgTX1 31 170 86 6,000
MgTx 144 675 230 ND

ND, not determined. All measurements in pM

table 2 Ki
Kv1.1 Kv1.2 Kv1.3 Kv1.6
HgTX1 0.08 0.09 0.24 8.7
MgTx 0.52 0.21 0.31 9.4

All measurements in pM

Mode of action

The mode of action is not yet known.Шаблон:Fact

References

Шаблон:Reflist

External links