STRUCTURAL STUDIES OF Sp1 AND YY1, AND TARGETS IN TFIID

提出的研究项目的主要目的是利用分子生物学和x射线晶体学方法的结合，在原子水平上阐明转录激活的机制。首先，我将专注于确定人类TAF(II)55以及人类TAF(II)55-TAF(II)250复合物的x射线结构，该复合物是预起始复合物的一部分，被认为是许多转录调节蛋白的靶标。然后，我将进行一系列实验，定量表征先前报道的已知转录调节因子（如Spl和YY1）的相互作用，并绘制这些与TAF(II)55-TAF(II)250异源二聚体直接相互作用的蛋白质的结构域。为了更详细地描述这些相互作用，我将尝试结晶化由TAFs和转录激活子的相互作用域组成的复合物，并解决它们的结构。这些研究将帮助我们了解癌症和关节炎中选择性的、特征明确的转录激活因子与起始前复合物中的基础因子相互作用以激活转录的机制。

The broad aim of the proposed research project is to elucidate the mechanisms of transcriptional activation at the atomic level using a combination of molecular biology and X-ray crystallography approaches. Initially, I will focus on determining the X-ray structure of human TAF(II)55 as well as the human TAF(II)55-TAF(II)250 complex, a part of the pre-initiation complex thought to be a target for a number of transcription regulatory proteins. I will then carry out a series of experiments to quantitatively characterize the previously reported interactions of known regulators of transcription, such as Spl and YY1, and map the domains of these proteins that interact directly with the TAF(II)55-TAF(II)250 heterodimer. In order to characterize these interactions in greater detail, I will attempt to crystallize the complexes composed of both TAFs as well as the interacting domains of the transcriptional activators, and solve their structures. The studies will help us understand the mechanisms by which selected, well-characterized transcriptional activators involved in cancer and arthritis interact with the basal factors in the pre-initiation complex to activate transcription.