Inostroza J, Flores O, Reinberg D
Department of Biochemistry, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Piscataway 08854.
J Biol Chem. 1991 May 15;266(14):9304-8.
Mammalian RNA polymerase II transcription factor IIE (TFIIE) was purified to apparent homogeneity. The activity copurified with polypeptides of 34 and 56 kDa. The 56-kDa subunit was sufficient for low levels of transcription activity in a transcription system reconstituted in vitro with highly purified general transcription factors and RNA polymerase II. The 34-kDa polypeptide was found to be stimulatory. The native molecular mass of TFIIE, as determined by gel filtration was estimated to be approximately 200 kDa, suggesting that TFIIE exists in solution as a tetramer composed of two 56-kDa and two 34-kDa polypeptides. Consistent with previous studies demonstrating an interaction of TFIIE with RNA polymerase II, we found that the entry of TFIIE into the transcription cycle was subsequent to the entry of RNA polymerase II.
哺乳动物RNA聚合酶II转录因子IIE（TFIIE）被纯化至表观均一性。该活性与34 kDa和56 kDa的多肽共纯化。在由高度纯化的通用转录因子和RNA聚合酶II体外重建的转录系统中，56 kDa亚基足以支持低水平的转录活性。发现34 kDa多肽具有刺激作用。通过凝胶过滤测定，TFIIE的天然分子量估计约为200 kDa，这表明TFIIE在溶液中以由两个56 kDa和两个34 kDa多肽组成的四聚体形式存在。与先前证明TFIIE与RNA聚合酶II相互作用的研究一致，我们发现TFIIE进入转录周期是在RNA聚合酶II之后。
