Identification and characterization of a novel O-superfamily conotoxin from Conus litteratus.
A novel conotoxin named lt6c, an O-superfamily conotoxin, was identified from the cDNA library of venom duct of Conus litteratus. The full-length cDNA contains an open reading frame encoding a predicted 22-residue signal peptide, a 22-residue proregion and a mature peptide of 28 amino acids. The signal peptide sequence of lt6c is highly conserved in O-superfamily conotoxins and the mature peptide consists of six cysteines arranged in the pattern of C-C-CC-C-C that is defined the O-superfamily of conotoxins. The mature peptide fused with thioredoxin, 6-His tag, and a Factor Xa cleavage site was successfully expressed in Escherichia coli. About 12 mg lt6c was purified from 1L culture. Under whole-cell patch-clamp mode, lt6c inhibited sodium currents on adult rat dorsal root ganglion neurons. Therefore, lt6c is a novel O-superfamily conotoxin that is able to block sodium channels.
State Key Laboratory of Biocontrol, Guangdong Province Key Laboratory of Pharmaceutical Functional Genes, Department of Biochemistry, College of Life Sciences, Sun Yat-sen (Zhongshan) University, Guangzhou, 510275, People's Republic of China.
Lei
L
Wang
Canhui
C
Pi
Junliang
J
Liu
Shangwu
S
Chen
Can
C
Peng
Dandan
D
Sun
Maojun
M
Zhou
Hui
H
Xiang
Zhenghua
Z
Ren
Anlong
A
Xu
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D020916:Conotoxins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics / Q000494:pharmacology; D052078:Conus Snail / Q000737:chemistry* / Q000235:genetics; D005260:Female; D008297:Male; D008969:Molecular Sequence Data; D005810:Multigene Family; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D051381:Rats; D011994:Recombinant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D017422:Sequence Analysis, DNA; D015222:Sodium Channels / Q000378:metabolism
D020916:Conotoxins; D011994:Recombinant Proteins; D015222:Sodium Channels