The 62- and 80-kDa subunits of transcription factor IIH mediate the interaction with Epstein-Barr virus nuclear protein 2.
The 62- and 80-kDa subunits of transcription factor IIH mediate the interaction with Epstein-Barr virus nuclear protein 2.
复制标题
DOI：
10.1073/pnas.92.8.3259
复制
发表时间：
1995-04
影响因子：
11.1
通讯作者：
Xiao Tong;Ronny Drapkin;Danny Reinberg;Elliott Kieff
中科院分区：
文献类型：
--
作者：
Xiao Tong;Ronny Drapkin;Danny Reinberg;Elliott Kieff
EBNA 2(Epstein-Barr病毒核抗原2)是一种酸性反式激活剂，对B淋巴细胞的EBV转化是必不可少的。我们发现EBNA 2与一般转录因子IIH直接相互作用。谷胱甘肽S转移酶-EBNA2酸性结构域融合蛋白抑制转录因子IIH的活性。TFIIH的p89(ERCC3)、p80(ERCC2)和p62亚基是GST-EBNA 2保留的蛋白。GST-EBNA 2小球的体外转录活性依赖于TFIIH。TFIIH的p62和p80亚基独立地与GST-EBNA 2结合，而TFIIH的p34亚基仅在p62存在的情况下结合。EBNA 2酸性结构域上的Trp-->；Thr突变在体内取消了EBNA 2的反式激活，并极大地削弱了EBNA 2与TFIIH活性以及与p62和p80亚基的关联，提供了EBNA 2反式激活与这些相互作用之间的联系。针对TFIIH p62亚基的抗体从EBV转化的B淋巴细胞中免疫共沉淀EBNA 2，表明EBNA 2在体内与TFIIH相关。
EBNA 2 (Epstein-Barr virus nuclear antigen 2) is an acidic transactivator essential for EBV transformation of B lymphocytes. We show that EBNA 2 directly interacts with general transcription factor IIH. Glutathione S-transferase (GST)-EBNA 2 acidic domain fusion protein depleted transcription factor IIH activity from a TFIIH nuclear fraction. The p89 (ERCC3), p80 (ERCC2), and p62 subunits of TFIIH were among the proteins retained by GST-EBNA 2. Eluates from the GST-EBNA 2 beads reconstituted activity in a TFIIH-dependent in vitro transcription assay. The p62 and p80 subunits of TFIIH independently bound to GST-EBNA 2, whereas the p34 subunit of TFIIH only bound in the presence of p62. A Trp-->Thr mutation in the EBNA 2 acidic domain abolishes EBNA 2 transactivation in vivo and greatly compromised EBNA 2 association with TFIIH activity and with the p62 and p80 subunits, providing a link between EBNA 2 transactivation and these interactions. Antibodies directed against the p62 subunit of TFIIH coimmunoprecipitated EBNA 2 from EBV-transformed B lymphocytes, indicating that EBNA 2 associates with TFIIH in vivo.