中文摘要：

【目的】获得原核表达的柑橘碎叶病毒（Citrus tatter leaf virus，CTLV）的外壳蛋白（Coat protein，CP）。【方法】以感染CTLV的柑橘叶片总RNA为模板，根据已报道CTLV设计引物，运用一步法RT—PCR对CTLV的CP进行扩增并克隆，并将CP克隆至表达载体pET28a（＋），转化大肠杆菌BL21（DE3），经异丙基硫代半乳糖苷（IPTG）诱导表达获得表达蛋白。【结果】扩增测序结果显示，克隆产物CP区域序列全长714bp，与已报道CP核苷酸序列（GenBank序列号：FJ223212）相似性达100％．推测编码238个氨基酸，表达蛋白的大小约27kD。重组质粒经IPTG诱导表达后，SDS—PAGE分析结果显示，重组质粒高效表达约30kD蛋白，酶联免疫吸附（Enzyme—linked immuno sorbent assay，ELISA）检测结果表明，该蛋白稀释5000倍仍能与苹果茎沟病毒（Apple stem grooving virus，ASGV）抗体发生阳性反应，证实表达蛋白为CTLV的CP。【结论】克隆了CTLV的CP，通过原核表达系统高效表达了CTLV的CP，为制备CTLV抗体奠定了基础。

英文摘要：

[Objective]The objective of the study was to obtain the coat protein of Citrus tatter leaf virus（CTLV） via the Prokaryotic Expression System. [Method]Total nucleic acids extracted from CTLV- infected trees were used as template for the amplification of CP gene by One-step reverse transcription PCR （RT-PCR） with a pair of specific primers. The fused expression plasmid was constructed by inserting the CP gene into the prokaryotic expression vector pET28a（＋） and then transformed into E. coli BL21 （DE3）. The recombined protein was expressed successfully after induced by isopropyl thiogalactoside （IPTG）. [ResultlSequence analysis showed that the length of CP gene was 714 base pairs, encoding 238 amino acid and expressing 27 kDa protein approximately. The sequenced CP gene showed 100% homology with the deposited CTLV CP gene （Accession No. at GenBank： FJ223212）. SDS-PAGE analysis indicated that an about 30 kDa expressed protein was obtained, which was consistent with that of expected protein. Positive reaction of expressed protein diluted 5 000 times with the Apple stem grooving virus antibody was observed by ELISA（enzyme-linked immuno sorbent assay）, suggesting the expressed protein was the coat protein of CTLV. [Conclusion]The CP gene of CTLV was successfully cloned and expressed in E. coli by Prokaryotic Expression System and the purified CP protein was suitable to the preparation of CTLV antibody.