Chibazakura T, Kitajima S, Yonaha M, Yasukochi Y
Department of Molecular Genetics, Tokyo Medical and Dental University, Japan.
Biochim Biophys Acta. 1994 Nov 22;1219(3):592-600. doi: 10.1016/0167-4781(94)90217-8.
The human general transcription factor IIF (TFIIF) is required for an accurate transcription initiation by RNA polymerase II and shares some analogous features with the sigma subunit of bacterial RNA polymerase. As an attempt to analyze the function of TFIIF, we examined its effect on bacterial transcription in vitro. TFIIF significantly enhanced the initiation of transcription by the bacterial RNA polymerase while other general transcription factors, TATA-binding protein, TFIIB, and TFIIE, did not. The enhancement of the bacterial transcription was ascribed to the 74 kDa subunit of TFIIF (RAP74). RAP74 had an activity of enhancing the binding of the bacterial RNA polymerase to the promoter. The enhancing activity of RAP74 depended on a low molar ratio of the RNA polymerase to the template DNA. The action of RAP74 in the bacterial transcription may be related to a possible regulatory role of RAP74 in the eukaryotic transcription initiation.
人类通用转录因子IIF（TFIIF）是RNA聚合酶II精确转录起始所必需的，并且与细菌RNA聚合酶的σ亚基具有一些类似的特征。作为分析TFIIF功能的一种尝试，我们在体外研究了它对细菌转录的影响。TFIIF显著增强了细菌RNA聚合酶的转录起始，而其他通用转录因子，如TATA结合蛋白、TFIIB和TFIIE则没有。细菌转录的增强归因于TFIIF的74 kDa亚基（RAP74）。RAP74具有增强细菌RNA聚合酶与启动子结合的活性。RAP74的增强活性取决于RNA聚合酶与模板DNA的低摩尔比。RAP74在细菌转录中的作用可能与RAP74在真核转录起始中可能的调节作用有关。
