中文摘要：

从蛙虹彩病毒（Rana grylio virus,RGV）中克隆出一个虹彩病毒科的序列保守基因RGV-12L,序列分析表明该基因全长894 bp,编码一个含297个氨基酸的多肽,分子量为33 kD。构建包含该基因全长的原核表达载体,进行原核表达,获得了分子量约53 kD的融合蛋白。将融合蛋白经腹腔注射免疫小鼠,制备出鼠抗RGV-12L血清。通过RT-PCR和Western blotting分析RGV感染细胞后RGV-12L的转录时序,感染4h可以在RNA水平检测到RGV-12L的转录,感染8h可以在蛋白水平检测到RGV-12L的表达。用DNA复制抑制剂阿糖胞苷（Arac）进行药物抑制实验,鉴定出RGV-12L是一个晚期基因。免疫荧光分析显示RGV-12L分布于感染细胞的细胞核和细胞质中,在病毒加工厂中也有该蛋白的分布,提示该基因可能与病毒的装配、释放有关。

英文摘要：

Rana grylio virus（RGV） is a member of the genus Ranavirus（family Iridoviridae） which type species is Frog Virus 3（FV3）.Viruses in Ranavirus can infect fish,amphibian and reptiles and result in high economic loss in aquaculture.Based on the previous studies on morphogenesis,cellular interaction,antigenicity comparison,restriction fragment length polymorphism and major capsid protein sequence analysis,RGV has been identified as an iridovirus similar to FV3.In the study,a sequence conserved gene（RGV-12L） of Iridoviridae was cloned and identified from RGV,it was 894 bp in length and encoded a protein of 297aa with a predicted molecular mass of 33 kD,Identities between RGV-12L and other viruses in Ranavirus ranged from 61.2% to 100% based on amino acid comparison.However,only 13.7% to 37.2% identities acquired when compared to viruses in Lymphocystivirus,Megalocytivirus and Chloriridovirus.The sequence had been submitted to GenBank and got a accession number of GQ849011.A recombinant prokaryotic expression plasmid pET32a-12L containing the fragment was constructed,and the plasmid was transformed into E.coli BL21（DE3）,and then the bacteria were induced by IPTG at a finally concentration of 1m mol/L and expressed a 53 kD fusion protein.The protein was purified from inclusion bodies under denaturing conditions using a His-Bind Purification Kit（Novagen）,mixed with an equal volume of Freund’s adjuvant（sigma） and used to immunize mice by hypoder-mal injection once every 7 days.After the fifth immunization,mice anti-RGV-12L serum was connected.The serum was used in Western blotting analysis and immunofluorescence observation.The temporal expression pattern RGV-12L was characterized during RGV infection by RT-PCR and Western blotting,the RGV-12L specific-fragment was barely detected at 4h postinfection（p.i.） and obviously at 8h p.i.,and its content increased to high level at 48h p.i..At protein level,a specific protein band was observed from 8h p.i.and increased to high level at 48h p.i..To f