柔嫩艾美耳球虫第二代裂殖子表面抗原基因(λMZ5-7)的克隆及序列分析

Sequence Analysis of λMZ5-7 Gene from Second Generation of Merozoites of Eimeria tenella

本文选择E .tenella第 2代裂殖子表面抗原基因 (λMZ5_7)为侯选抗原基因 ,利用RT_PCR方法从E .tenella第 2代裂殖子中扩增出了λMZ5_7基因 ,把这一片段克隆到PGEM_T_easy克隆载体上 ,得到的阳性克隆经PCR鉴定及酶切分析。结果表明 ,重组子 (PGEM_T_λMZ)中含有λMZ5_7基因 ,且是正向插入的。核苷酸序列分析结果表明 ,该序列全长 984bp ,有一个开放阅读框 (933bp) ,与国外报道的λMZ5_7基因比较 ,同源性为 98.8% ,只是在 335～ 347bp处缺少 12bp ,其余部分相同 ,缺少的 12bp没有造成氨基酸编码的错位 ,缺少的 4个氨基酸为Thr、Ser、Gln、Gln。

A surface antigen λMZ5_7 gene of Eimeria tenella merozoites was cloned by PCR from the synthesized first strand cDNA.The PCR products were analysed by agarose electrophoresis and then cloned into pGEM_T_easy vector successfully.The specific recombinant plasmid was identified with restriction endonuclease analysis and sequenced by automatic DNA sequencer.The results indicated λMZ5_7 gene was 984 in length and included an open reading frame encodes a protein of 311 amino acid residues.Comparison of λMZ5_7 gene we gained with the previously reported λMZ5_7 gene indicated two genes had a high homology of 98.8% and λMZ5_7 gene we gained deleted 12 nucleotides compared with the reported λMZ5_7 gene,but the deleted 12 nucleotides didn't result in change of open reading frame.