New conotoxins define the novel I3-superfamily.
We purified two novel conotoxins, designated as ca11a and ca11b, from the venom of Conus caracteristicus. Based on the amino acid sequence of mature ca11a, we cloned its full-length cDNA. Based on the signal peptide of ca11a, several ca11a-like conotoxins were cloned from C. caracteristicus and C. pulicarius. These novel conotoxins have an I-superfamily cysteine pattern but with a novel signal peptide sequence, suggesting they belong to a new branch of I-superfamily, designated as I(3)-superfamily. Additionally, two O-superfamily conotoxins were also cloned based on the signal peptide of ca11a, suggesting a possible evolutionary relationship between O- and I-superfamilies.
Institute of Protein Research, College of Life Sciences and Technology, Tongji University, Shanghai, PR China.
Duo-Duo
DD
Yuan
Li
L
Liu
Xiao-Xia
XX
Shao
Can
C
Peng
Cheng-Wu
CW
Chi
Zhan-Yun
ZY
Guo
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002852:Chromatography, Ion Exchange; D003001:Cloning, Molecular; D020916:Conotoxins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D017931:DNA Primers; D018076:DNA, Complementary; D008969:Molecular Sequence Data; D008978:Mollusk Venoms / Q000737:chemistry*; D017386:Sequence Homology, Amino Acid
D020916:Conotoxins; D017931:DNA Primers; D018076:DNA, Complementary; D008978:Mollusk Venoms