Mechanisms of core promoter recognition by general transcription factor TFIID

TFIID是由TBP和14个TAFs组成的最大的GTF，在TATA缺失启动子的转录过程中起着关键作用。在后生动物中，除TATA元件外，其他几个核心启动子元件(CE)被认为是TFIID的识别位点。然而，目前还不清楚酵母中TATA缺失启动子中是否也存在功能上的同源元件，因此我们建立了一种以VTC1为报告基因的高通量筛选系统来检测酵母中的基因表达。这种方法使我们能够通过筛选Cyc1启动子的随机寡核苷酸池来分离几种活性的和新的CE。TAF1蛋白的TAF N末端结构域(TAND)在转录激活中起重要作用。TAND由TAND1和TAND2两个亚区组成，分别与TBP的凹面和凸面相互作用。与其他团队合作，我们确定了Tand-TBP复合体的晶体结构，为转录激活提供了新的视角。

TFIID, the largest GTF composed of TBP and 14 TAFs, plays a critical role in transcription from TATA-less promoters. In metazoans, several core promoter elements (CE) other than the TATA element are thought to be recognition sites for TFIID. However, it is unclear whether functionally homologous elements also exist in TATA-less promoters in yeast.Here we develop a novel high-throughput screening system to measure gene expression in yeast by using VTC1 as a reporter gene. This method allows us to isolate several active and novel CE by screening a randomized oligonucleotide pool for the CYC1 promoter. The TAF N-terminal domain (TAND) of the TAF1 protein plays a significant role in transcriptional activation. TAND comprises two subdomains, TAND1 and TAND2, which interact with the concave and convex surfaces of TBP, respectively. In collaboration with other groups, we determine the crystal structure of the TAND-TBP complex that provides a novel insight into transcriptional activation.