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.
Wang
Lei
L
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.
Pi
Canhui
C
Liu
Junliang
J
Chen
Shangwu
S
Peng
Can
C
Sun
Dandan
D
Zhou
Maojun
M
Xiang
Hui
H
Ren
Zhenghua
Z
Xu
Anlong
A
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