Simmen K A, Bernués J, Parry H D, Stunnenberg H G, Berkenstam A, Cavallini B, Egly J M, Mattaj I W
European Molecular Biology Laboratory, Heidelberg, FRG.
EMBO J. 1991 Jul;10(7):1853-62. doi: 10.1002/j.1460-2075.1991.tb07711.x.
We present evidence that transcription factor TFIID, known for its central role in transcription by RNA polymerase II, is also involved in RNA polymerase III transcription of the human U6 snRNA gene. Recombinant human TFIID, expressed either via a vaccinia virus vector in HeLa cells or in Escherichia coli, affects U6 transcription in three different in vitro assays. First, TFIID-containing fractions stimulate U6 transcription in reactions containing rate-limiting amounts of HeLa nuclear extract. Second, TFIID addition relieves transcriptional exclusion between two competing U6 templates. Third, TFIID can replace one of two heat labile fractions essential for U6 transcription. Thus, at least one basal transcription factor is involved in transcription by two different RNA polymerases.
我们提供的证据表明,转录因子TFIID,因其在RNA聚合酶II转录中的核心作用而闻名,也参与了人类U6 snRNA基因的RNA聚合酶III转录。通过痘苗病毒载体在HeLa细胞中或在大肠杆菌中表达的重组人TFIID,在三种不同的体外试验中影响U6转录。首先,含TFIID的组分在含有限速量HeLa核提取物的反应中刺激U6转录。其次,添加TFIID可缓解两个竞争性U6模板之间的转录排斥。第三,TFIID可以替代U6转录所必需的两个热不稳定组分之一。因此,至少一种基础转录因子参与了两种不同RNA聚合酶的转录。