Cone snail venom peptide Vc1.1 selectively blocks human α9 and α3β2 nicotinic receptors involved in pain | Research

The takeaway

α-Conotoxin Vc1.1 from cone snail venom selectively antagonized human α9 (IC50=160 nM) and α3β2 (IC50=232 nM) nicotinic receptors, with molecular dynamics revealing key binding determinants relevant to neuropathic and inflammatory pain treatment.

160 nM selective α9 blockade
Cone snail venom peptide Vc1.1 selectively targets α9 nicotinic receptors involved in neuroinflammation at nanomolar potency—a template for non-opioid pain drugs

What the researchers found

Vc1.1: selective for hα9 (IC50=160 nM) and hα3β2 (IC50=232 nM). α9[N179A]: 20-fold ↓potency (lost H-bond with D11). β2[E86A]: 4-fold ↑potency (K104 interaction). α9[N213K]: 2-fold ↑potency. MD simulations: D5 side chain interactions altered.

Why it matters

α9 nAChRs mediate neuroinflammation and pain. A selective venom peptide that blocks these receptors provides a template for developing non-opioid pain treatments.

How the study worked

Two-electrode voltage clamp in Xenopus oocytes expressing human nAChR subtypes. Site-directed mutagenesis (α9, β2). Molecular dynamics simulations. IC50 determination.

What this study cannot tell us

Oocyte expression may not fully replicate native receptor pharmacology. Human subtype selectivity may differ from rat. In vivo pain data only in rats. Manufacturing of disulfide-rich peptides is complex.

How to read the evidence

Rigorous electrophysiology and molecular dynamics study. Strong structure-activity data for rational drug design.

When this study was published

Published in 2025.

The bigger picture

Cone snail venoms have already yielded one FDA-approved pain drug (ziconotide). Vc1.1's selective blockade of α9 nAChRs for neuroinflammatory pain could lead to another venom-derived analgesic.

Questions still open

Can Vc1.1 analogues be designed with improved α9 selectivity?
Would intranasal or intrathecal delivery enable clinical use?
How does α9 blockade compare to CGRP blockade for neuropathic pain?

Common questions

Can snail venom treat pain?

Cone snails produce potent peptide toxins that block pain receptors. Vc1.1, a 16-amino acid peptide from Conus victoriae, blocks specific nicotinic receptors (α9) involved in neuroinflammation and pain at very low concentrations. One cone snail peptide (ziconotide) is already an approved pain drug.

Why is α9 receptor selectivity important?

α9 nicotinic receptors are specifically involved in neuroinflammation and pain signaling. Blocking them could provide pain relief without the addiction risk of opioids or the broad side effects of drugs targeting more common receptor subtypes. Vc1.1's natural selectivity for α9 makes it an ideal starting point for drug design.

Read the original research

Molecular determinants of the selectivity and potency of α-conotoxin Vc1.1 for human nicotinic acetylcholine receptors.

The Journal of biological chemistry, 301(1), 108017

View on PubMed ↗Publisher’s paper ↗

Citation

Tae, Han-Shen; Hung, Andrew; Clark, Richard J; Adams, David J. (2025). Molecular determinants of the selectivity and potency of α-conotoxin Vc1.1 for human nicotinic acetylcholine receptors.. The Journal of biological chemistry, 301(1), 108017. https://doi.org/10.1016/j.jbc.2024.108017