Margottin F, Dujardin G, Gérard M, Egly J M, Huet J, Sentenac A
Département de Biologie, Centre d'Etudes Nucléaires de Saclay, Gif-sur-Yvette, France.
Science. 1991 Jan 25;251(4992):424-6. doi: 10.1126/science.1989075.
Fractionation of transcription extracts has led to the identification of multiple transcription factors specific for each form of nuclear RNA polymerase. Accurate transcription in vitro of the yeast U6 RNA gene by RNA polymerase C requires at least two factors. One of them was physically and functionally indistinguishable from transcription factor IID (TFIID or BTF1), a pivotal component of polymerase B transcription complexes, which binds to the TATA element. Purified yeast TFIID (yIID) or bacterial extracts that contained recombinant yIID were equally competent to direct specific transcription of the U6 gene by RNA polymerase C. The results suggest the formation of a hybrid transcription machinery, which may imply an evolutionary relation between class B and class C transcription factors.
转录提取物的分级分离已导致鉴定出对每种形式的核RNA聚合酶具有特异性的多种转录因子。RNA聚合酶C在体外准确转录酵母U6 RNA基因至少需要两种因子。其中一种在物理和功能上与转录因子IID（TFIID或BTF1）无法区分，TFIID是聚合酶B转录复合物的关键组分，它与TATA元件结合。纯化的酵母TFIID（yIID）或含有重组yIID的细菌提取物同样能够指导RNA聚合酶C对U6基因进行特异性转录。结果表明形成了一种混合转录机制，这可能意味着B类和C类转录因子之间存在进化关系。
