来自东亚钳蝎的一种兴奋性昆虫选择性神经毒素的cDNA序列。

The cDNA sequence of an excitatory insect selective neurotoxin from the scorpion Buthus martensi Karsch.

作者信息

Xiong Y M, Ling M H, Lan Z D, Wang D C, Chi C W

机构信息

State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry, Academia Sinica, China.

出版信息

Toxicon. 1999 Feb;37(2):335-41. doi: 10.1016/s0041-0101(98)00176-7.

DOI:10.1016/s0041-0101(98)00176-7

PMID:10078863

Abstract

The full-length cDNA of an excitatory insect selective neurotoxin was amplified from total cDNAs of venomous glands of the scorpion Buthus martensi Karsch (BmK) using the 3'RACE and 5'RACE (rapid amplification of cDNA ends, RACE) method and sequenced. The cDNA encoded a precursor of the insect toxin of 88 amino acid residues, including a signal peptide of 18 residues and a mature toxin of 70 residues. The cDNA deduced sequence of this toxin was homologous with the determined amino acid sequence of BmK IT1, an excitatory insect toxin purified from the scorpion venom, except for three different residues, two at the positions 24-25, and another in the COOH-terminus of the toxin. Among them the COO-terminal residue Gly in the cDNA deduced sequence was predominantly different from the conserved residue Asn found in other known scorpion excitatory insect toxins.

摘要

采用3'RACE和5'RACE（cDNA末端快速扩增）方法，从东亚钳蝎（BmK）毒腺的总cDNA中扩增出一种兴奋性昆虫选择性神经毒素的全长cDNA，并进行测序。该cDNA编码一种含88个氨基酸残基的昆虫毒素前体，包括一个18个残基的信号肽和一个70个残基的成熟毒素。除了三个不同的残基外，该毒素的cDNA推导序列与从蝎毒中纯化出的兴奋性昆虫毒素BmK IT1的已确定氨基酸序列同源，其中两个位于24 - 25位，另一个位于毒素的COOH末端。其中，cDNA推导序列中的COOH末端残基甘氨酸与其他已知蝎兴奋性昆虫毒素中发现的保守残基天冬酰胺明显不同。