Vilcek S, Paton D, Lowings P, Björklund H, Nettleton P, Belák S
Department of Virology, The National Veterinary Institute, Biomedical Center, Uppsala, Sweden.
Virus Genes. 1999;18(2):107-14. doi: 10.1023/a:1008000231604.
Specific PCR primers were selected for each pestivirus genotype which flanked the 3'-part of the NS5B gene and more than three quarters of the 3'-UTR. PCR products were sequenced in both directions using an automatic sequencing device and analyzed by computer package program DNASTAR. A comparative analysis of the 3' untranslated region (3'-UTR) of 82 viruses, representing the four genotypes of the Pestivirus genus, provided a similar phylogenetic grouping as other genomic regions. Intertypic recombination was not observed, but Border disease virus (BDV) and Bovine viral diarrhoea virus type I (BVDV I) showed great intragenotypic variability. In most pestiviruses the stop codon is TGA, but BDV isolates were found to have either a TAG or a TAA stop codon. Various deletions and insertions were observed in the 3'-UTR region. Viruses of the BVDV lb group contained a characteristic deletion of 41 nucleotides. Compared to the 5'-UTR, the 3'-UTR was less conserved. The first 50-60 nucleotides were particularly variable, whilst the most conserved part was found at the 3' end of the studied region. All 82 viruses contained AT-rich stretches, the positions and sizes of which differed between the genotypes.
针对每种瘟病毒基因型选择了特异性PCR引物，这些引物位于NS5B基因的3'端部分以及3'非翻译区（3'-UTR）超过四分之三的区域两侧。使用自动测序设备对PCR产物进行双向测序，并通过计算机软件包DNASTAR进行分析。对代表瘟病毒属四种基因型的82种病毒的3'非翻译区（3'-UTR）进行的比较分析，提供了与其他基因组区域相似的系统发育分组。未观察到型间重组，但边界病病毒（BDV）和牛病毒性腹泻病毒I型（BVDV I）表现出很大的型内变异性。在大多数瘟病毒中，终止密码子是TGA，但发现BDV分离株具有TAG或TAA终止密码子。在3'-UTR区域观察到各种缺失和插入。BVDV lb组病毒包含一个41个核苷酸的特征性缺失。与5'-UTR相比，3'-UTR的保守性较差。前50-60个核苷酸特别可变，而最保守的部分位于研究区域的3'端。所有82种病毒都含有富含AT的片段，其位置和大小在不同基因型之间有所不同。
