In this work, a novel M-superfamily conotoxin, designated lt3a, was purified from the crude venom of Conus litteratus. Combined with peptide sequencing, MALDI-TOF mass spectrometry and cDNA cloning techniques, the amino acid sequence of lt3a was supposed to be DγCCγ OQWCDGACDCCS, where O is hydroxyproline and γ is carboxyglutamate. The Cys framework of lt3a (-CC-C-C-CC-) is similar to that of ψ-, μ-, κM-conotoxins, which are representatives of M-conotoxins. Peptide lt3a is categorized into M1 branch based on the number of residues in the last Cys loop. Whole cell patch-clamp study on adult rat dorsal root ganglion neurons indicated that lt3a could enhance tetrodotoxin-sensitive sodium currents. This is a previously unknown function of M-superfamily conotoxins.
- Conus litteratus
- M-superfamily conotoxin
- Post-translational modification
- Rat dorsal root ganglion neurons
- Tetrodotoxin-sensitive sodium channels
ASJC Scopus subject areas
- Health, Toxicology and Mutagenesis