Overview
Cys15 – C-terminal amidation
- Luo, S. et al. (2013) J Med Chem., 56, 9655.
Alomone Labs Alpha-Conotoxin TxID inhibits α3/β4 nAChR heterologously expressed in Xenopus oocytes.A. Time course of Alpha-Conotoxin TxID (#STC-110) action on α3/β4 nAChR currents, elicited every 50 sec by a transient application of 20 µM ACh, while membrane potential was held at -80 mV. Application of 50 nM (green) and 500 nM (magenta) Alpha-Conotoxin TxID significantly inhibits the currents.
B. Superimposed traces of α3/β4 nAChR currents evoked by ACh (arrow) after application of control, 50 nM (green) and 500 nM (magenta) Alpha-Conotoxin TxID (taken from the recording in A.
α-Conotoxin TxID (a-CTx TxID) is a 15 amino acid peptidyl toxin isolated from the mollusk-hunting cone snail, Conus textile. This toxin belongs to the α-4/6 conotoxin (α-CTx) subfamily, that potently blocks the α3β4 nicotinic acetylcholine receptor (nAChR) subtype with high selectivity. In addition, α-CTx TxID blocks the closely related α6/α3β4 nAChR but exhibits minimal activity towards other nAChR subtypes. α-CTx TxID is the most potent α3β4 nAChR antagonist characterized thus far and has a unique selectivity profile 1.
Neuronal nAChRs are widely distributed throughout the central and peripheral nervous systems. These receptors play important roles in normal physiology and are involved in many diseases such as epilepsy, pain, addiction, Alzheimer's disease, Parkinson's disease, schizophrenia, as well as breast and lung carcinoma. The α3β4 nAChR is the most prevalent subtype in the brain and is associated with nicotine addiction, neuropathic pain and small cell lung cancer2.
Given the diverse functions of the nAChRs, the a-CTx TxID may be a valuable tool for elucidating the distinct roles of the α3β4 nAChRs in a variety of normal and pathological processes1,3. a-CTx TxID has been used for these purposes and it was recently shown to exhibit anti-tumor activity, which may provide novel strategies for cancer treatment4.
Alpha-conotoxin TxID (#STC-110) is a highly pure, synthetic and biologically active peptide toxin.