【摘要】 中华狼蛛与穴居狼蛛在进化上亲缘性较近,均属于狼蛛科狼蛛属。该研究从中华狼蛛毒腺cDNA文库筛选到与穴居狼蛛抗肿瘤肽LSTX-A1的前体序列(或cDNA序列)具有高度相似性的3个毒素多肽(LS-toxin-A1、LS-toxin-A2、LS-toxin-A3)。与LSTX-A1比较,由于发生同义突变使得它们与LSTX-A1的信号肽和中间肽的氨基酸序列完全相同。而在成熟肽区域,由于非同义突变导致LS-toxin-A1和LS-toxin-A2与LSTX-A1的氨基酸序列不同;但LS-toxin-A3仅发生同义突变,因此它与LSTX-A1的氨基酸序列相同。这些中华狼蛛毒素的成熟肽含有4对二硫键(其排列方式为-C-C-CC-C-C-C-C-),而且它们在C末端残基均发生酰胺化修饰。由于该研究鉴定的中华狼蛛毒素与LSTX-A1具有极高的序列相似性,因此作者推断它们具有类似的抗肿瘤活性。更多还原

【Abstract】 Lycosa sinensis is closely related to Lycosa singoriensis in the evolution and they belong to the genus Lycosa(family Lycosidae). In the present study, three toxin peptides(LS-toxin-A1, LS-toxin-A2, and LS-toxin-A3) were screened from cDNA library of L. sinensis venom glands, their precursor sequences(or cDNA sequences) of which have highly similarity with an antitumor peptide LSTX-A1 from the venom of wolf spider L. singoriensis. Compared with amino acid sequences of signal peptide and propeptide, they have identical sequences with LSTX-A1 because of synonymous mutation. In amino acid sequences of mature peptides, LS-toxin-A1 and LS-toxin-A2 have different sequences with LSTX-A1 because of non-synonymous mutation, but LS-toxin-A3 has the same sequence as LSTX-A1 for only synonymous mutation. Their mature peptides contain four pairs of disulfide bonds arranged in the form of-C-C-CC-C-C-C-C-, and there is amidation modification at the C-terminal residue. We conclude that three toxin peptides have similar antitumor activity because they exhibit extremely high sequence similarity with LSTX-A1.更多还原