BOVINE LEUKEMIA-VIRUS TRANSCRIPTION IS CONTROLLED BY A VIRUS-ENCODED TRANS-ACTING FACTOR AND BY CIS-ACTING RESPONSE ELEMENTS
BOVINE LEUKEMIA-VIRUS TRANSCRIPTION IS CONTROLLED BY A VIRUS-ENCODED TRANS-ACTING FACTOR AND BY CIS-ACTING RESPONSE ELEMENTS
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DOI：
10.1128/jvi.61.8.2462-2471.1987
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发表时间：
1987-08-01
影响因子：
5.4
通讯作者：
DERSE, D
中科院分区：
文献类型：
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作者：
DERSE, D
牛白血病病毒（BLV）基因表达在多个水平上受到精细调控，包括受病毒编码的反式作用因子和顺式作用靶序列影响的转录控制。与人类T细胞白血病病毒I型和II型相似，但与其他RNA肿瘤病毒不同，BLV在其基因组的3“末端含有几个开放阅读框。编码来自该区域的两个重叠阅读框的亚基因组mRNA可以产生38和18千道尔顿（kDa）的蛋白质。使用转染的病毒基因构建体以不同的组合进行的一系列顺-反实验表明，表达38-kDa蛋白质对于反式激活BLV启动子是必要且足够的。这种激活对BLV长末端重复序列是特异性的，因为各种相关的逆转录病毒启动子对38 kDa蛋白p38（XBL）的表达没有反应。缺失分析和嵌合启动子的构建鉴定了一个75个碱基对长的末端重复区，其功能类似于p38（XBL）依赖性增强子元件。
Bovine leukemia virus (BLV) gene expression is exquisitely regulated at multiple levels, including a transcriptional control effected by virus-encoded trans-acting factors and cis-acting target sequences. Like the human T-cell leukemia viruses type I and type II, but unlike other RNA tumor viruses, BLV contains several open reading frames at the 3'' end of its genome. A subgenomic mRNA which encodes two overlapping reading frames from this region could produce proteins of 38 and 18 kilodaltons (kDa). A series of cis-trans experiments using transfected virus gene constructs in different combinations revealed that expression of the 38-kDa protein was both necessary and sufficient to activate, in trans, the BLV promoter. This activation was specific for the BLV long terminal repeat, as a variety of related retroviral promoters were not responsive to the expression of the 38-kDa protein p38(XBL). Deletion analysis and construction of chimeric promoters identified a 75-base-pair long terminal repeat region which functions like a p38(XBL)-dependent enhancer element.