Cloning of novel conotoxin precursor sequences from Conus pulicarius

Conotoxins are small peptides in the venoms of Conus genus with various phy siological activities targeting ion channels and receptors in the neuromusc ular system. Applying a modified 3'-RACE (Rapid Amplification of cDNA Ends) strategy, two novel precursor cDNA sequences were cloned from a small verm ivorous cone snail, Conus pulicarius. The predicted mature peptides were na med conotoxin PuIA, and PuIIA respectively. Conotoxin PuIA consists of 30 r esidues of amino acids and conotoxin PuIIA 28. Both the two conotoxins have the same cysteine framework and are believed to be members of the O-superf amily conotoxins.