Snake venom three-finger neurotoxin (3FTx)

Snake venom three-finger neurotoxins (3FTxs) are a major family of non-enzymatic proteins found in the venom of elapid snakes, including the Indian Cobra (Naja naja) and Common Krait (Bungarus caeruleus). These toxins are characterized by a conserved structural scaffold consisting of three beta-stranded loops projecting from a central hydrophobic core, resembling three fingers of a hand. Their primary biological function is to induce paralysis by binding with high affinity to nicotinic acetylcholine receptors (nAChR) at the neuromuscular junction, thereby blocking cholinergic transmission. In the context of Indian elapid envenomation, 3FTxs are the principal drivers of life-threatening neurotoxicity and respiratory failure. Therapeutic intervention primarily involves the administration of polyvalent antivenoms, which contain antibodies that neutralize these toxins. Recent advancements include the development of synthetic human antibodies, such as 95Mat5, which target conserved regions of the 3FTx family to provide broad-spectrum protection against diverse elapid venoms.

Other names

Three-finger toxin3FTxα-neurotoxinPost-synaptic neurotoxinCuraremimetic toxinSnake venom three-finger toxin

Neutralization of the toxin's ability to bind to host receptors, such as the nicotinic acetylcholine receptor (nAChR), by antibody-mediated sequestration or competitive inhibition of the toxin's functional loops.