Human TATA binding protein inhibits human papillomavirus type 11 DNA replication by antagonizing E1-E2 protein complex formation on the viral origin of replication.
Human TATA binding protein inhibits human papillomavirus type 11 DNA replication by antagonizing E1-E2 protein complex formation on the viral origin of replication.
复制标题
人 TATA 结合蛋白通过拮抗病毒复制起点上 E1-E2 蛋白复合物的形成来抑制人乳头瘤病毒 11 型 DNA 复制。
DOI：
10.1128/jvi.76.10.5014-5023.2002
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发表时间：
2002
影响因子：
5.4
通讯作者：
Alexander,KennethA
中科院分区：
文献类型：
--
作者：
Hartley,KellyA;Alexander,KennethA
人乳头瘤病毒（HPV）蛋白E2在病毒生命周期中具有双重作用。通过与基底角质形成细胞中的宿主转录因子直接相互作用，E2促进病毒转录。随着角质形成细胞分化的进展，E2与病毒解旋酶E1结合，以激活植物病毒DNA复制。在角质形成细胞分化过程中，E2的主要作用如何从转录转换为复制尚不清楚，但在病毒复制起点附近存在TATA位点使我们假设TATA结合蛋白（TBP）可能影响HPV复制。在这里，我们表明，C-末端结构域的TBP（TBPc）是一个有效的抑制剂E2刺激的HPV DNA复制在体外（50%抑制浓度= 0.56 nM）。增加E1浓度不能克服TBPc在复制试验中的抑制，表明TBPc是E1结合的非竞争性抑制剂。虽然可以证明E2-TBPc的直接关联，但这种相互作用不能完全解释TBPc介导的病毒复制抑制的机制。由于E2支持E1与viralori的序列特异性结合，因此我们提出TBPc通过抑制E2-DNA结合间接拮抗E1-oriassociation。事实上，TBPc在不存在（Ki= 0.5 ± 0.1 nM）和存在（Ki= 0.6 ± 0.3 nM）E1的情况下有效拮抗E2与DNA的结合。由于E2和TBPc不能在病毒序列上相邻，TBPc和E2之间的直接DNA结合竞争是复制抑制的原因。鉴于TBPc在体外抑制HPV DNA复制的能力和数据表明TBPc拮抗E2-oriassociation，我们建议转录因子调节HPV DNA复制以及病毒转录。
The human papillomavirus (HPV) protein E2 possesses dual roles in the viral life cycle. By interacting directly with host transcription factors in basal keratinocytes, E2 promotes viral transcription. As keratinocyte differentiation progresses, E2 associates with the viral helicase, E1, to activate vegetative viral DNA replication. How E2's major role switches from transcription to replication during keratinocyte differentiation is not understood, but the presence of a TATA site near the viral origin of replication led us to hypothesize that TATA-binding protein (TBP) could affect HPV replication. Here we show that the C-terminal domain of TBP (TBPc) is a potent inhibitor of E2-stimulated HPV DNA replication in vitro (50% inhibitory concentration = 0.56 nM). Increasing the E1 concentration could not overcome TBPc inhibition in replication assays, indicating that TBPc is a noncompetitive inhibitor of E1 binding. While direct E2-TBPc association could be demonstrated, this interaction could not fully account for the mechanism of TBPc-mediated inhibition of viral replication. Because E2 supports sequence-specific binding of E1 to the viralori, we proposed that TBPc antagonizes E1-oriassociation indirectly through inhibition of E2-DNA binding. Indeed, TBPc potently antagonized E2 binding to DNA in the absence (Ki= 0.5 ± 0.1 nM) and presence (Ki= 0.6 ± 0.3 nM) of E1. Since E2 and TBPc cannot be coadjacent on viral sequences, direct DNA-binding competition between TBPc and E2 was responsible for replication inhibition. Given the ability of TBPc to inhibit HPV DNA replication in vitro and data indicating that TBPc antagonized E2-oriassociation, we propose that transcription factors regulate HPV DNA replication as well as viral transcription.