Transcription of the Epstein-Barr virus genome during latency in growth-transformed lymphocytes.
Transcription of the Epstein-Barr virus genome during latency in growth-transformed lymphocytes.
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EB病毒基因组在生长转化淋巴细胞潜伏期的转录。
DOI：
10.1128/jvi.64.4.1667-1674.1990
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发表时间：
1990
影响因子：
5.4
通讯作者：
Kieff,E
中科院分区：
文献类型：
--
作者：
Sample,J;Kieff,E
核连续试验揭示了在体外感染的人胎儿淋巴母细胞（IB-4）中潜伏感染期间EB病毒基因组的广泛转录。EBER基因是这些细胞中转录最多的病毒基因。它们的转录在每毫升1微克α-鹅膏蕈碱存在下被部分抑制，在100微克/毫升时被完全抑制，与RNA聚合酶III转录一致。所有其他转录在1微克α-鹅膏蕈碱/ml时被抑制，这与RNA聚合酶II对α-鹅膏蕈碱的敏感性一致。除了EBER转录之外，U1区域几乎没有发生转录。具体地，没有检测到来自U1潜伏启动子的转录。RNA聚合酶II转录在IR1中最高，通过U2和IR2延伸到U3结构域并逐渐降低，但在整个基因组的其余部分都是可测量的。这与IR1内的EBNA基因转录起始一致。与编码EBNA-3A、EBNA-3B或EBNA-3C或EBNA-1的结构域相反，编码EBNA-LP和EBNA-2的IR1和U2结构域的更高水平的转录与更高水平的EBNA-LP/EBNA-2 mRNA相关。转录从U4延伸到U5，即使没有已知的潜伏基因mRNA从EBNA-1开放阅读框的U4下游表达。这可能是由于EBNA基因转录的无效终止。潜伏膜蛋白启动子的Left3转录低于EBNA转录，尽管潜伏膜蛋白mRNA是最丰富的潜伏基因mRNA，表明该mRNA被更有效地加工或具有更长的半衰期。虽然从DL强早期启动子检测到转录，并在较小程度上从其他早期启动子，早期mRNA比EBNA mRNA丰度低或检测不到，这表明在这些潜伏感染的细胞中可能存在转录后以及转录控制早期mRNA表达。
Nuclear run-on assays revealed extensive transcription of the Epstein-Barr virus genome during latent infection in in vitro-infected human fetal lymphoblastoid cells (IB-4). The EBER genes were the most heavily transcribed viral genes in these cells. Their transcription was partially inhibited in the presence of 1 microgram of alpha-amanitin per ml and fully inhibited at 100 micrograms/ml, consistent with RNA polymerase III transcription. All other transcription was inhibited at 1 microgram of alpha-amanitin per ml, consistent with RNA polymerase II sensitivity to alpha-amanitin. Other than EBER transcription, almost no transcription occurred from the U1 region. Specifically, no transcription was detected from the U1 latent promoter. RNA polymerase II transcription was highest in IR1, extending rightward through U2 and IR2 into the U3 domain and gradually decreased, but was measurable throughout the rest of the genome. This is consistent with EBNA gene transcription initiation within IR1. The higher level of transcription of the IR1 and U2 domains, which encode EBNA-LP and EBNA-2, as opposed to the domains which encode EBNA-3A, EBNA-3B, or EBNA-3C or EBNA-1, correlated with a higher level of EBNA-LP/EBNA-2 mRNA. Transcription extended through U4 into U5, even though no known latent-gene mRNAs are expressed from U4 downstream of the EBNA-1 open reading frame. This may result from inefficient termination of EBNA gene transcription. Leftward transcription from the latent membrane protein promoter was lower than EBNA transcription, although the latent membrane protein mRNA was the most abundant of the latent-gene mRNAs, indicating that this mRNA is more efficiently processed or has a longer half-life. Although transcription was detected from the DL strong early promoters and to a lesser extent from other early promoters, early mRNAs were less abundant than EBNA mRNAs or undetectable, suggesting that there may be posttranscriptional as well as transcriptional control over early mRNA expression in these latently infected cells.