Alpha-Conotoxin CnIA

**Semantic type:** Hazardous or Poisonous Substance

**Definition:** A 14-amino acid alpha3/5-conotoxin isolated from the venom of the cone snail Conus consors that is a competitive antagonist of the muscle-type nicotinic acetylcholine receptors, blocking synaptic transmission at the neuromuscular junction. Alpha-conotoxins are identified by a characteristic arrangement of four-cysteine residues (-CC-C-C-) and disulfide bonding of Cys1-Cys3 and Cys2-Cys4. In addition, alpha3/5-conotoxins are further classified as having three residues in the first intercysteine loop and five residues in the second intercysteine loop.

**Synonyms:** - ALPHA-CONOTOXIN CNIA - Alpha-CnIA - Alpha-CnIA