Different toxins acting on Kv1.3 channel have been isolated from animal venom. MeuKTX toxin from Mesobuthus eupeus phillipsi scorpion and shtx-k toxin from Stichodactyla haddoni sea anemone have been identified as two effective Kv1.3 channel blockers. In this work, we characterized the genomic organization of both toxins. MeuKTX gene contains one intron and two exons, similar to the most scorpion toxins. There are a few reports of genomic structure of sea anemone toxins acting on Kv channels. The sequence encoding mature peptide of shtx-k was located in an exon separated by an intron from the coding exon of the propeptide and signal region. In order to make a peptide with more affinity for Kv1.3 channel and greater stability, the shtx-k/ MeuKTX chimeric peptide was designed and constructed using splicing by overlap extension-PCR (SOE-PCR) method. MeuKTX, shtx-k, and shtx-k/MeuKTX were cloned and the expression of the soluble proteins in E. coli was determined. Molecular docking studies indicated more inhibitory effect of shtx-k/MeuKTX on Kv1.3 channel compared to shtx-k and MeuKTX toxins. Key amino acids binding channel from both toxins, also involved in interaction of chimeric peptide with channel. Our results showed that the fusion peptide, shtx-k/MeuKTX could be an effective agent to target Kv1.3 channel.

从动物毒液中分离出作用于Kv1.3通道的不同毒素。来自Mesobuthus eupeus phillipis蝎子的 MeuKTX 毒素和来自Stichodactyla haddoni的 shtx-k 毒素海葵已被确定为两种有效的 Kv1.3 通道阻滞剂。在这项工作中，我们描述了两种毒素的基因组组织。MeuKTX基因含有一个内含子和两个外显子，类似于大多数蝎毒。有一些关于海葵毒素作用于 Kv 通道的基因组结构的报道。编码 shtx-k 成熟肽的序列位于由内含子与前肽和信号区的编码外显子隔开的外显子中。为了制备对Kv1.3通道更亲和、稳定性更高的肽，采用重叠延伸-PCR(SOE-PCR)方法设计构建了shtx-k/ MeuKTX嵌合肽。克隆 MeuKTX、shtx-k 和 shtx-k/MeuKTX 并在大肠杆菌中表达可溶性蛋白被确定了。分子对接研究表明，与 shtx-k 和 MeuKTX 毒素相比，shtx-k/MeuKTX 对 Kv1.3 通道的抑制作用更强。两种毒素的关键氨基酸结合通道，也参与嵌合肽与通道的相互作用。我们的研究结果表明，融合肽 shtx-k/MeuKTX 可以成为靶向 Kv1.3 通道的有效药物。