MOLECULAR ANALYSIS OF A YEAST TRANSCRIPTIONAL REGULATOR

建议项目的长远目标是阐明 一种必需酵母MOT1的作用机制及体内功能 通过解离TATA结合蛋白来调节转录的蛋白质 (TBP)-DNA复合体以依赖于ATP的方式。MOT1是一个 进化保守的核蛋白大家族(The SNF2/SWI2家族)参与转录、DNA修复、重组、 和染色体分离。中国汉族人SNF2/SWI2家族成员突变研究 人类已被确定为Cockayne综合征的原因，X连锁 智力低下和阿尔法地中海贫血。尽管无处不在 SNF2/SWI2家族成员的发生及其作用的分子机制 这些蛋白质中的哪一种还不清楚，也不知道是什么 这些蛋白质中的大多数在体内发挥作用。 将使用生化、分子生物学和遗传学方法来 详细定义MOT1如何与TBP相互作用，以及它的ATPase如何 用来驱动TBP-DNA复合体的解离。这些方法将 也可用于鉴定体内与MOT1相互作用的其他蛋白质 并确定了决定MOT1‘S效应大小的参数 关于个体基因在体内的表达。建议的分析 MOT1功能将有助于更好地理解MOT1作为 以及对SNF2/SWI2家族功能的更好理解 全体议员。拟议的工作还将提供一个框架， SNF2/SWI2家族其他成员的分析 目前对此知之甚少。

The long-term objectives of the proposed project are to elucidate the mechanism of action and in vivo function of MOT1, an essential yeast protein that regulates transcription by dissociating TATA-binding protein (TBP)-DNA complexes in an ATP-dependent manner. MOT1 is a member of a large and growing family of evolutionarily conserved nuclear proteins (the SNF2/SWI2 family) involved in transcription, DNA repair, recombination, and chromosome segregation. Mutation of SNF2/SWI2 family members in humans have been identified as the causes of Cockayne's syndrome, X-linked mental retardation, and alpha-thalassemia. Despite the ubiquitous occurrence of SNF2/SWI2 family members, the molecular mechanisms of action of these proteins are not understood in detail, nor is it understood what roles most of these proteins play in vivo. Biochemical, molecular biological and genetic approaches will be used to define in molecular detail how MOT1 interacts with TBP, and how its ATPase is utilized to drive TBP-DNA complex dissociation. These approaches will also be used to identify other proteins that MOT1 interacts with in vivo and to define the parameters that determine the magnitude of MOT1's effect on the expression of individual genes in vivo. The proposed analysis of MOT1 function will lead to a better understanding of the role of MOT1 as well as a better understanding of the functions of SNF2/SWI2 family members in general. The proposed work will also provide a framework for the analysis of other SNF2/SWI2 family members whose activities are currently poorly understood.