Sequence comparison of JSRV with endogenous proviruses: Envelope genotypes and a novel ORF with similarity to a G-protein-coupled receptor
Sequence comparison of JSRV with endogenous proviruses: Envelope genotypes and a novel ORF with similarity to a G-protein-coupled receptor
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DOI：
10.1006/viro.1999.9728
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发表时间：
1999-06-05
期刊：
影响因子：
3.7
通讯作者：
DeMartini, JC
中科院分区：
文献类型：
--
作者：
Bai, JR;Bishop, JV;DeMartini, JC
绵羊肺癌是绵羊的一种传染性肺癌，由致癌的Jaagsiekte绵羊逆转录病毒(JSRV)引起，JSRV与绵羊内源性逆转录病毒序列(ESRV)密切相关。利用外源病毒特异的U3寡核苷酸引物，从肿瘤DNA中扩增出JSRV前病毒全基因组或其3‘端片段。对这些前病毒序列的分析发现，POL编码区有一个新的开放阅读框(ORF)，命名为ORF X，它在ESRV和JSRV序列中非常保守。ORF X的推导氨基酸与哺乳动物腺苷受体亚型3的一部分相似，腺苷受体亚型是G蛋白偶联受体家族的成员。对来自三大洲的6个JSRV毒株的env氨基酸进行比较，确定了15个残基，定义了JSRV的两种不同的基因类型。序列分析发现，JSRV和ESRV在env(TM)跨膜区和长端重复序列(U3)上有两个高度可变区，由此衍生出JSRV特异性DNA探针。通过在Southern杂交中使用这些DNA探针，我们首次在存在多个ESRV位点的情况下成功地鉴定了肿瘤基因组DNA中的JSRV前病毒序列，验证了外源病毒特异性DNA探针在分析致癌前病毒整合位点和鉴定整合的外源前病毒序列中的使用，(C)1999学术出版社。
Ovine pulmonary carcinoma, a contagious lung cancer of sheep, is caused by the oncogenic jaagsiekte sheep retrovirus (JSRV) that is closely related to a family of endogenous sheep retroviral sequences (ESRVs). By using exogenous virus-specific U3 oligonucleotide primers, the entire JSRV proviral genome or its 3' part was amplified from tumor DNA. Analysis of these proviral sequences revealed a novel open reading frame (ORF) within the pol coding region, designated ORF X, which was well conserved in ESRV and JSRV sequences. Deduced amino acids of ORF X showed similarity to a portion of the mammalian adenosine receptor subtype 3, a member of the G-protein-coupled receptor family. Comparison of deduced env amino acids of six JSRV strains from three continents identified 15 residues that defined two distinct genotypes of JSRVs. Sequence analysis identified two highly variable regions between JSRV and ESRV in the transmembrane domain of env (TM) and the 3' unique sequence (U3) of the long terminal repeat, from which JSRV-specific DNA probes were derived. By using these DNA probes in Southern hybridization, for the first time we successfully identified JSRV proviral sequences in tumor genomic DNA in the presence of multiple ESRV loci, validating the use of exogenous virus-specific DNA probes in the analysis of oncogenic proviral integration sites and identification of integrated exogenous proviral sequences, (C) 1999 Academic Press.