title: Cloning and characterization of a novel calcium channel toxin-like gene BmCa1 from Chinese scorpion Mesobuthus martensii Karsch.
abstract: Many studies have been carried on peptides and genes encoding scorpion toxins from the venom of Mesobuthus martensii Karsch (synonym: Buthus martensii Karsch, BmK), such as Na+, K+ and Cl- channel modulators. In this study, a novel calcium channel toxin-like gene BmCa1 was isolated and characterized from the venom of Mesobuthus martensii Karsch. First, a partial cDNA sequence of the Ca2+ channel toxin-like gene was identified by random sequencing method from a venomous gland cDNA library of Mesobuthus martensii Karsch. The full-length sequence of BmCa1 was then obtained by 5'RACE technique. The peptide deduced from BmCa1 precursor nucleotide sequence contains a 27-residue signal peptide and a 37-residue mature peptide. Although BmCa1 and other scorpion toxins are different at the gene and protein primary structure levels, BmCa1 has the same precursor nucleotide organization and cysteine arrangement as that of the first subfamily members of calcium channel scorpion toxins. Genomic DNA sequence of BmCa1 was also cloned by PCR. Sequence analysis showed that BmCa1 gene consists of three exons separated by two introns of 72 bp and 1076 bp in length, respectively. BmCa1 is the first calcium channel toxin-like gene cloned from the venom of Mesobuthus martensii Karsch and potentially represents a novel class of calcium channel toxins in scorpion venoms.
authors.affiliation: State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, PR China. zjcao@whu.edu.cn
authors.forename: Cao
authors.initials: C
authors.lastname: Zhijian
authors.forename: Xie
authors.initials: X
authors.lastname: Yun
authors.forename: Dai
authors.initials: D
authors.lastname: Chao
authors.forename: Zhu
authors.initials: Z
authors.lastname: Shunyi
authors.forename: Yin
authors.initials: Y
authors.lastname: Shijin
authors.forename: Wu
authors.initials: W
authors.lastname: Yingliang
authors.forename: Li
authors.initials: L
authors.lastname: Wenxin
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015220:Calcium Channels / Q000737:chemistry; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000378:metabolism; D005091:Exons; D015723:Gene Library; D007438:Introns; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012604:Scorpion Venoms / Q000737:chemistry*; D012605:Scorpions; D017386:Sequence Homology, Amino Acid
chemical_list: D015220:Calcium Channels; D018076:DNA, Complementary; D012604:Scorpion Venoms