Replication and Transcription Activator (RTA) of Murine Gammaherpesvirus 68 Binds to an RTA-Responsive Element and Activates the Expression of ORF18
Replication and Transcription Activator (RTA) of Murine Gammaherpesvirus 68 Binds to an RTA-Responsive Element and Activates the Expression of ORF18
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鼠丙型疱疹病毒 68 的复制和转录激活剂 (RTA) 与 RTA 响应元件结合并激活 ORF18 的表达
DOI：
10.1128/jvi.00561-11
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发表时间：
2011-08
影响因子：
5.4
通讯作者：
Deng, Hongyu
中科院分区：
文献类型：
--
作者：
Hong, Yun;Qi, Jing;Gong, Danyang;Han, Chuanhui;Deng, Hongyu
RTA （replication and transcription activator，复制转录激活子）主要由开放阅读框50编码，是一种即时早期基因产物，在所有特征的伽玛疱疹病毒中都是保守的。以往的研究表明，eb病毒（EBV）和卡波西肉瘤相关疱疹病毒（KSHV）的RTA蛋白可以通过直接或间接的机制激活许多病毒早期裂解基因的启动子。小鼠γ疱疹病毒68 （MHV-68）与KSHV和EBV有遗传关系，来自MHV-68的RTA同源物也启动基因表达的裂解循环。虽然在MHV-68中发现了两个依赖RTA的启动子，但RTA与启动子相互作用的机制尚未确定。在这项研究中，我们首先通过报告基因分析在MHV-68的裂解复制区左侧起源处发现了一个rta应答启动子，并通过系统删除绘制了一个27 bp的rta应答元件（RRE）。有趣的是，序列分析在该区域发现了第二个RRE。电泳迁移率转移实验（EMSA）和染色质免疫沉淀（ChIP）实验表明，RTA在体外或体内均可直接与这两种RREs结合。诱变研究进一步表征了介导RTA与EMSA结合的重要核苷酸。此外，我们设计了rre缺失的病毒，并在病毒基因组的背景下证明，其中一种RREs介导了rta依赖性的基本裂解基因ORF18的激活，在新感染期间。据我们所知，这是首次鉴定出MHV-68中的RTA结合位点。由于ORF18调控病毒晚期基因表达，我们的研究也有助于描述γ疱疹病毒裂解基因的表达级联。
ABSTRACT The replication and transcription activator (RTA), mainly encoded by open reading frame 50, is an immediate-early gene product that is conserved among all characterized gammaherpesviruses. Previous studies have demonstrated that RTA proteins of Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) can activate the promoter of many viral early lytic genes through direct or indirect mechanisms. Murine gammaherpesvirus 68 (MHV-68) is genetically related to KSHV and EBV, and the RTA homologue from MHV-68 also initiates the lytic cycle of gene expression. Although two RTA-dependent promoters had been identified in MHV-68, the mechanism of the interaction between RTA and the promoters was not characterized. In this study, we first identified an RTA-responsive promoter in the left origin of lytic replication region of MHV-68 through a reporter assay and mapped a 27-bp RTA-responsive element (RRE) through systematic deletions. Interestingly, sequence analysis identified a second RRE in this region. An electrophoretic mobility shift assay (EMSA) and a chromatin immunoprecipitation (ChIP) assay showed that RTA can bind directly to these two RREs in vitro or in vivo. Mutagenesis studies have further characterized the nucleotides important for mediating RTA binding by an EMSA. Moreover, we engineered RRE-deleted viruses and demonstrated in the context of the viral genome that one of the RREs mediates the RTA-dependent activation of an essential lytic gene, ORF18, during de novo infection. To our knowledge, this is the first time that RTA binding sites in MHV-68 have been identified. Since ORF18 regulates viral late gene expression, our study has also contributed to the delineation of the expression cascade of gammaherpesvirus lytic genes.
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影响因子：
5.4
作者：
Yan Wang;Hong Li;Man Yee Chan;F. Zhu;D. Lukac;Yan Yuan
通讯作者：
Yan Wang;Hong Li;Man Yee Chan;F. Zhu;D. Lukac;Yan Yuan
RTA 启动子去甲基化和组蛋白乙酰化调节鼠伽马疱疹病毒 68 重新激活。
影响因子：
3.7
作者：
Yang Z;Tang H;Huang H;Deng H
通讯作者：
Deng H
影响因子：
5.4
作者：
Arumugaswami, Vaithilingaraja;Wu, Ting-Ting;Sun, Ren
通讯作者：
Sun, Ren
影响因子：
5.4
作者：
Tingting Wu;L. Tong;T. Rickabaugh;S. Speck;R. Sun
通讯作者：
Tingting Wu;L. Tong;T. Rickabaugh;S. Speck;R. Sun
影响因子：
14.9
作者：
GRUFFAT, H;SERGEANT, A
通讯作者：
SERGEANT, A