EWS, but not EWS-FLI-1, is associated with both TFIID and RNA polymerase II:: Interactions between two members of the TET family, EWS and hTAFII68, and subunits of TFIID and RNA polymerase II complexes
EWS, but not EWS-FLI-1, is associated with both TFIID and RNA polymerase II:: Interactions between two members of the TET family, EWS and hTAFII68, and subunits of TFIID and RNA polymerase II complexes
复制标题
DOI：
10.1128/mcb.18.3.1489
复制
发表时间：
1998-03-01
影响因子：
5.3
通讯作者：
Tora, L
中科院分区：
文献类型：
--
作者：
Bertolotti, A;Melot, T;Tora, L
与Ewing肉瘤和原始神经外胚层肿瘤特异性相关的t（11;22）染色体易位导致嵌合分子将EWS基因的氨基末端编码区与fl -1基因编码的羧基末端dna结合域融合。由于EWS基因编码的蛋白的功能尚不清楚，我们通过比较EWS与其结构同源物hTAF(II)68的活性来研究EWS在RNA聚合酶II （Pol II）转录中的可能作用。我们证明EWS的一部分能够与基础转录因子TFIID相关联，该转录因子由tata结合蛋白（TBP）和TBP相关因子（TAF(II)s）组成。体外结合研究表明，EWS和hTAF(II)68与相同的TFIID亚基相互作用，这表明EWS和hTAF(II)68存在于同一个TFIID复合体中可能是相互排斥的。此外，EWS不仅与TFIID相关，而且与hTAF(II)68相似，也与Pol II复合物相关。Pol II的亚基与EWS和hTAF(II)68相互作用，证实了与聚合酶的关联。与EWS相反，EWS- fl -1融合蛋白与Ewing细胞核提取物中的TFIID或Pol II均不相关。这些结果表明EWS和EWS- fl -1可能在Pol II转录中发挥不同的作用。
The t(11;22) chromosomal translocation specifically linked to Ewing sarcoma and primitive neuroectodermal tumor results in a chimeric molecule fusing the amino-terminus-encoding region of the EWS gene to the carboxyl-terminal DNA-binding domain encoded by the FLI-1 gene. As the function of the protein encoded by the EWS gene remains unknown, we investigated the putative role of EWS in RNA polymerase II (Pol II) transcription by comparing its activity with that of its structural homolog, hTAF(II)68. We demonstrate that a portion of EWS is able to associate with the basal transcription factor TFIID, which is composed of the TATA-binding protein (TBP) and TBP-associated factors (TAF(II)s). In vitro binding studies revealed that both EWS and hTAF(II)68 interact with the same TFIID subunits, suggesting that the presence of EWS and that of hTAF(II)68 in the same TFIID complex may be mutually exclusive. Moreover, EWS is not exclusively associated with TFIID but, similarly to hTAF(II)68, is also associated with the Pol II complex. The subunits of Pol II that interact with EWS and hTAF(II)68 have been identified, confirming the association with the polymerase. In contrast to EWS, the tumorigenic EWS-FLI-1 fusion protein is not associated with either TFIID or Pol II in Ewing cell nuclear extracts. These observations suggest that EWS and EWS-FLI-1 may play different roles in Pol II transcription.