中文摘要：

【目的】采用电子克隆技术克隆红鳍东方纯组织蛋白酶L基因，并应用生物信息学技术分析其推导氨基酸的序列特征，为进一步探索其在免疫功能中的作用奠定基础。【方法】以斑马鱼的组织蛋白酶L核苷酸序YIJ（Y08321．1）为探针，对红鳍东方纯基因组数据库进行BLASTn分析，将检索到的匹配结果进行碱基3’端及5端的适当延长，用DNAssist预测其编码信息；然后从GenBank获取若干物种组织蛋白酶L序列，用DNASTAR软件进行比对。【结果】红鳍东方纯组织蛋白酶【基因全长2005bp，含7个外显子和6个内含子；包含编码336个氨基酸的开放阅读框（1011bp）；其推导的氨基酸序列具有组织蛋白酶L所特有的氨基酸保守结构域（ERwNIN和GNFD）及由Cys25、His159和Asnm残基组成的保守活性位点，与青鲻、鲤鱼的组织蛋白酶【基因具有较高的序列一致性。【结论】红鳍东方纯组织蛋白酶L的一些结构域和催化活性位点在进化过程中比较保守，与鱼类物种来源的组织蛋白酶L在氨基酸水平上一致性较高，在进化上亲缘关系较近。

英文摘要：

[Objective]This research aimed to clone the cathepsin L gene from Takifugu rub@es through in Silico cloning and to analyze the characteristics of the predicted amino acid sequence by the bioinformatics methods in order to provide bases for further studies related to the function of cathepsin L in the immunity system. [ Method ] BLASTn was processed in the database of T. rubr/pes using the cathepsin L nucleotide sequence of Zebrafish （Y08321.1） as a probe; the matching sequences were subsequentially extended in the 3＇ and 5＇ direction, respectively. The coding information was estimated by DNAssist. An alignment with other cathepsin L sequences from GenBank was performed by DNASTAR. [Result] The predicted cathepsin L gene was 2005 bp in length, which contained 7 exons and 6 introns. It also contained an open reading frame （ORF） of 1011 bp encoding a polypeptide of 336 amino acids. The predicted amino acid sequence contained a catalytic triad formed by Cys~, His1s9, Asn17s, and the conserved ERWNIN, GNFD motifs, which were all characteristics of cathepsin L. Homology analysis revealed that the deduced amino acid sequence of T. rubripes cathepsin L shared high percentage of identity compared to other species viz., Oryzias latipes and carp. [Conclusion]The motifs and catalytic active sites of T. rubHpes cathepsin L were rather conserved. The T. rubffpes cathepsin L shared high percentage of identity with other fish cathepsin L in the amino acid level, which was also close to other fish cathepsin L in respect to evolutionary developments.