东方巴贝斯虫核糖体蛋白L26全长cDNA克隆及蛋白特性分析

目的克隆东方巴贝斯虫核糖体蛋白L26（RPL26）全长cDNA序列,对编码的蛋白特性进行分析,并探讨它们在研究系统发育中的应用。方法采用经EST测序获得的东方巴贝斯虫RPL26的5′特异性引物及文库载体3′通用引物对东方巴贝斯虫cDNA文库进行扩增,测序获得东方巴贝斯虫RPL26全长cDNA序列。用BLASTX程序搜索相似性序列及保守结构域,所获序列在GenBank中登记,并用Neighbor-Joining（N-J）法构建基于L26氨基酸序列的系统发育树。结果东方巴贝斯虫RPL26全长cDNA序列（GenBank登录号为FJ492804）长度为716 bp,开放阅读框为414 bp,编码137个氨基酸;同源性分析结果表明东方巴贝斯虫RPL26序列较保守,与牛巴贝斯虫（Babesia bovis）、小泰勒虫（Theileria par-va）等亲缘关系较近,在系统发育树中的遗传距离也较近。结论首次获得东方巴贝斯虫RPL26基因,其可能作为分子指标应用于研究生物系统发育。

Cloning and characterization analysis of full length cDNA of ribosomal protein L26 of Babesia orientalis

Objective To clone the full length cDNA sequence of ribosomal protein L26 （RPL26） of B. orientalis, and analyse its characterization. Methods The full length cDNA sequence of RPL26 was obtained by amplification from the cDNA library of B. orientalis by using the specific 5＇ primer of RPL26 EST and 3＇ universal primer. The protein sequence was analysed by BLASTX in GenBank, and the phylogenetic tree （N-J） was constructed based on amino acid sequences of RPL26 of B. orientalis and other organisms. Results The full length is 716 bp （GenBank accession number： FJ4928（M） , and the open reading frame was 414 bp, encoding 127 amino acids. The BLASTX analysis showed that the amino acid sequences of RPL26 was conserved during evolution, and the phylogenetic tree showed that its genetic distance was close to B. bovis and Theileria parva. Conclusions RPL26 of B. orientalis is obtained for the first time, and RPL26 may be useful in the study of phylogenetic relationships between organisms and ribosomal protein.