RNA polymerase II-associated protein (RAP) 74 binds transcription factor (TF) IIB and blocks TFIIB-RAP30 binding
RNA polymerase II-associated protein (RAP) 74 binds transcription factor (TF) IIB and blocks TFIIB-RAP30 binding
复制标题
DOI：
10.1074/jbc.271.20.11703
复制
发表时间：
1996-05-17
影响因子：
4.8
通讯作者：
Burton, ZF
中科院分区：
文献类型：
--
作者：
Fang, SM;Burton, ZF
构建了一组人RNA聚合酶II相关蛋白（RAP）30（转录因子IIF的小亚基（TFIIF; RAP 30/74））的缺失突变体，以定位功能结构域。测试突变体的准确转录活性、RAP 74结合和TFIIB结合。转录测定表明N-和C-末端序列对于RAP 30功能的重要性。RAP 74结合RAP 30的N-末端区域的氨基酸1和98之间。TFIIB结合RAP 30的重叠区，定位于氨基酸1-176（氨基酸27-152包含最小结合区）。RAP 74的C末端区（氨基酸358-517）直接且独立地结合TFIIB。有趣的是，RAP 74通过结合TFIIB和通过结合RAP 30两者来阻断TFIIB-RAP 30结合。因此，当TFIIF复合物完整时，TFIIB TFIIF接触通过RAP 74维持。如果TFIIB-RAP 30相互作用在生理上很重要，则TFIIF复合物必须在某些转录复合物内解离。
A set of deletion mutants of human RNA polymerase II-associated protein (RAP) 30, the small subunit of transcription factor IIF (TFIIF; RAP30/74), was constructed to map functional domains. Mutants were tested for accurate transcriptional activity, RAP74 binding, and TFIIB binding. Transcription assays indicate the importance of both N- and C-terminal sequences for RAP30 function. RAP74 binds to the N-terminal region of RAP30 between amino acids 1 and 98. TFIIB binds to an overlapping region of RAP30, localized to amino acids 1-176 (amino acids 27-152 comprise a minimal binding region), The C-terminal region of RAP74 (amino acids 358-517) binds directly and independently to TFIIB, Interestingly, RAP74 blocks TFIIB-RAP30 binding, both by binding TFIIB and by binding RAP30. When the TFIIF complex is intact, therefore, TFIIB TFIIF contact is maintained through RAP74. If the TFIIB-RAP30 interaction is physiologically important, the TFIIF complex must dissociate within some transcription complexes.