Direct interactions between Epstein-Barr virus leader protein LP and the EBNA2 acidic domain underlie coordinate transcriptional regulation.
Direct interactions between Epstein-Barr virus leader protein LP and the EBNA2 acidic domain underlie coordinate transcriptional regulation.
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Epstein-Barr 病毒前导蛋白 LP 和 EBNA2 酸性结构域之间的直接相互作用是协调转录调控的基础。
DOI：
10.1073/pnas.0307808100
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
Harada,Shizuko
中科院分区：
文献类型：
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作者：
Peng,Chih-Wen;Xue,Yong;Zhao,Bo;Johannsen,Eric;Kieff,Elliott;Harada,Shizuko
EB病毒核前导蛋白LP（EBNALP）和EBNA 2首先在淋巴细胞感染中表达，协调调节细胞和病毒基因转录，并且对于淋巴细胞生长成淋巴母细胞样细胞系（LCL）至关重要。我们现在已经发现，EBNALP很容易与EBNA 2或EBNA 2的C-末端酸性激活结构域（E2 AD）时，这两个组件表达的细菌。在淋巴母细胞中，EBNALP和EBNA 2没有稳定的关联。然而，EBNALP仅缺失了与淋巴母细胞中的EBNA 2或细菌中的EBNA 2酸性激活结构域稳定相关的10个C-末端氨基酸。EBNALP共激活淋巴母细胞中的潜伏膜蛋白1启动子，E2 AD是必不可少的; EBNALP可以与EBNA 2缺陷突变体EBNA 2 W 454 T共激活，但不能与E2 AD缺失的EBNA 2共激活。此外，EBNALP 31个氨基酸（dW 2 Y1）与24个C-或N-末端氨基酸是一个特异性和有效的亲和基质EBNA 2或EBNALP。甚至EBNALP 22-aa肽dW 2也特异性结合EBNALP或EBNA 2。EBNALP和EBNA 2之间的这些生物化学相互作用仅在相互作用不稳定时才能协调成淋巴细胞中细胞和病毒基因表达的转录调控; EBNALP C-末端10 aa的缺失稳定了与EBNA 2的结合并阻止了共激活。由于EBNALPd 10主要抑制EBNALP与EBNA 2的共激活，因此EBNALPd 10在LCL中的表达可能有助于评估EBNALP共激活在LCL生长或存活中的作用。
The Epstein–Barr virus nuclear leader protein LP (EBNALP) and EBNA2 are expressed first in lymphocyte infection, coordinately regulate cell and viral gene transcription, and are critical for lymphocyte outgrowth into lymphoblastoid cell lines (LCLs). We have now found that EBNALP readily associated with EBNA2 or with the EBNA2 C-terminal acidic activation domain (E2AD) when both components were expressed by bacteria. In lymphoblasts, EBNALP and EBNA2 did not stably associate. However, EBNALP deleted for only 10 C-terminal amino acids stably associated with EBNA2 in lymphoblasts or with EBNA2 acidic activating domain from bacteria. The E2AD was essential for EBNALP coactivation of the latent membrane protein 1 promoter in lymphoblasts; EBNALP could coactivate with a deficient mutant EBNA2, EBNA2W454T, but not with EBNA2 deleted for E2AD. Moreover, EBNALP 31 amino acids (dW2Y1) with 24 C- or N-terminal amino acids was a specific and efficient affinity matrix for EBNA2 or EBNALP. Even an EBNALP 22-aa peptide, dW2, specifically bound EBNALP or EBNA2. These biochemical interactions between EBNALP and EBNA2 enable coordinated transcriptional regulation of cell and viral gene expression in lymphoblasts only when the interaction is unstable; deletion of the EBNALP C-terminal 10 aa stabilized association with EBNA2 and prevented coactivation. Because EBNALPd10 dominantly inhibited EBNALP coactivation with EBNA2, EBNALPd10 expression in LCLs may be useful in assessing the role of EBNALP coactivation in LCL growth or survival.