Architecture of replication compartments formed during Epstein-Barr virus lytic replication
Architecture of replication compartments formed during Epstein-Barr virus lytic replication
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DOI：
10.1128/jvi.79.6.3409-3418.2005
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发表时间：
2005-03-01
影响因子：
5.4
通讯作者：
Tsurumi, T
中科院分区：
文献类型：
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作者：
Daikoku, T;Kudoh, A;Tsurumi, T
爱泼斯坦-巴尔病毒（EBV）的DNA复制发生在细胞核中称为复制区室的离散位点。在这项研究中，我们对复制区室的结构进行了全面的分析。BZLF1或ilyt结合蛋白在诱导的早期阶段在细胞核中表现出精细的弥漫性分布模式，然后在裂解感染期间与复制室中的复制EBV基因组相关。BMRF1聚合酶（Pol）加工因子在复制室中呈均匀分布，与新合成的病毒DNA完全一致。用磷酸（一种病毒DNA Pol抑制剂）抑制病毒DNA复制，消除了BMRF1蛋白的DNA结合形式，尽管该蛋白在细胞中充分表达。这些观察结果以及几乎所有丰富表达的BMRF1蛋白都以DNA结合形式存在的发现表明，BMRF1蛋白不仅作为Pol过程因子在病毒复制叉上起作用，而且广泛分布在新复制的EBV基因组DNA上。相比之下，BALF5 Pol催化蛋白、BALF2单链dna结合蛋白和BBLF2/3蛋白（解旋酶-引物酶复合体的一个组成部分）被共定位为不同的点，分布在复制室中，代表病毒复制工厂。细胞复制工厂是基于非染色质核结构和核基质构建的，而病毒复制工厂很容易被dna酶I溶解。因此，与细胞DNA复制相比，EBV裂解DNA复制工厂将更简单，从而使复制结构域的构建更加轻松。
Epstein-Barr virus (EBV) productive DNA replication occurs at discrete sites, called replication compartments, in nuclei. In this study we performed comprehensive analyses of the architecture of the replication compartments. The BZLF1 oriLyt binding proteins showed a fine, diffuse pattern of distribution throughout the nuclei at immediate-early stages of induction and then became associated with the replicating EBV genome in the replication compartments during lytic infection. The BMRF1 polymerase (Pol) processivity factor showed a homogenous, not dot-like, distribution in the replication compartments, which completely coincided with the newly synthesized viral DNA. Inhibition of viral DNA replication with phosphonoacetic acid, a viral DNA Pol inhibitor, eliminated the DNA-bound form of the BMRF1 protein, although the protein was sufficiently expressed in the cells. These observations together with the findings that almost all abundantly expressed BMRF1 proteins existed in the DNA-bound form suggest that the BMRF1 proteins not only act at viral replication forks as Pol processive factors but also widely distribute on newly replicated EBV genomic DNA. In contrast, the BALF5 Pol catalytic protein, the BALF2 single-stranded-DNA binding protein, and the BBLF2/3 protein, a component of the helicase-primase complex, were colocalized as distinct dots distributed within replication compartments, representing viral replication factories. Whereas cellular replication factories are constructed based on nonchromatin nuclear structures and nuclear matrix, viral replication factories were easily solubilized by DNase I treatment. Thus, compared with cellular DNA replication, EBV lytic DNA replication factories would be simpler so that construction of the replication domain would be more relaxed.