A family of disulfide-knotted spider peptides, several of which block the pain channel Nav1.7.
Also known as: HWTX · HwTx-IV · mu-theraphotoxin-Hs2a
Part of the Foundational & therapeutic peptides cluster
Overview
Huwentoxins are a family of neurotoxic peptides from the venom of the Chinese bird spider, most sharing the highly stable inhibitor cystine-knot (ICK) fold. Different members target voltage-gated calcium or sodium channels; huwentoxin-IV, for example, selectively blocks tetrodotoxin-sensitive sodium channels including Nav1.7. This makes them valuable research tools for studying pain signaling. This page is educational and not medical advice.
Source & context
Biological / chemical source: Venom of the Chinese bird spider (Cyriopagopus schmidti / Haplopelma schmidti)
Primary research or clinical context: Research tools for ion-channel and pain studies
Cystine-knot scaffold
Most huwentoxins fold into an inhibitor cystine knot, in which three disulfide bonds form a ring threaded by a third bridge. This gives exceptional stability across pH and temperature, a property that makes ICK peptides attractive templates for engineering selective, protease-resistant channel modulators.
Channel targets and pain research
Individual huwentoxins act on N-type calcium channels or on voltage-gated sodium channels. Huwentoxin-IV inhibits Nav1.7, a channel central to pain sensation, so it is studied as a probe and lead for non-opioid analgesic research. These remain investigational tools rather than approved medicines.
FAQ about Huwentoxin
What is Huwentoxin?+
Huwentoxins are a family of neurotoxic peptides from the venom of the Chinese bird spider, most sharing the highly stable inhibitor cystine-knot (ICK) fold. Different members target voltage-gated calcium or sodium channels; huwentoxin-IV, for example, selectively blocks tetrodotoxin-sensitive sodium channels including Nav1.7. This makes them valuable research tools for studying pain signaling. This page is educational and not medical advice.
Is Huwentoxin an approved medicine?+
Huwentoxin is discussed here as a research / educational topic. Research tools for ion-channel and pain studies. This is not medical advice.
What is the typical length of Huwentoxin?+
Huwentoxin is not a classic amino-acid chain peptide in the same sense; see the profile for classification details.