Zhao Xiangrong, Buehring Gertrude C
Graduate Program in Endocrinology, 3060 Valley Life Science Building, University of California, Berkeley, CA 94720-3140, USA.
Virology. 2007 Sep 15;366(1):150-65. doi: 10.1016/j.virol.2007.03.058. Epub 2007 May 11.
Bovine leukemia virus (BLV) is an oncogenic virus widespread in cattle. It belongs to the genus Deltaretrovirus of the family Retroviridae along with human and simian T-lymphotropic viruses. Here we report the addition of 28 new sequences to the current literature of 16 full-length BLV envelope gene sequences. The phylogenetic clustering, genotyping, and geographic distribution of BLV env variations corresponded in most cases. Most natural variations are mapped to the surface of the proposed conformational models of BLV gp51 N-terminus and gp30 external domain, overlapping with or adjacent to immunogenic epitopes. Analyses for evidence of possible selection pressures suggest the BLV env is under stringent negative selection overall, while strong positive selection is indicated for immunogenic epitope G. Natural env deletions bounded by similar flanking sequences were observed in multiple isolates and would result in truncated signal peptides, missing gp51, and aberrant coding frames for other proteins.
牛白血病病毒（BLV）是一种在牛群中广泛传播的致癌病毒。它与人类和猿猴T淋巴细胞白血病病毒同属于逆转录病毒科的δ逆转录病毒属。在此，我们报告在现有16个全长BLV包膜基因序列文献的基础上新增了28个新序列。BLV env变异的系统发育聚类、基因分型和地理分布在大多数情况下是一致的。大多数自然变异位于所提出的BLV gp51 N端和gp30外部结构域构象模型的表面，与免疫原性表位重叠或相邻。对可能的选择压力证据的分析表明，总体而言BLV env处于严格的负选择之下，而免疫原性表位G则显示出强烈的正选择。在多个分离株中观察到由相似侧翼序列界定的自然env缺失，这将导致信号肽截断、gp51缺失以及其他蛋白质的编码框异常。
