Greene J M, Kingston R E
Department of Molecular Biology, Massachusetts General Hospital, Boston 02114.
Mol Cell Biol. 1990 Apr;10(4):1319-28. doi: 10.1128/mcb.10.4.1319-1328.1990.
We have characterized the interactions between the TATA element and other sequence elements of a human heat shock protein 70 (hsp70) promoter by a mutational approach. Expression of a distal element of this promoter requires an intact TATA element in human cell lines. The hsp70 TATA element can be functionally replaced for this interaction by TATA elements from the simian virus 40 early and adenovirus EIIa promoters. The TATA element in this promoter therefore both determines the appropriate start site and determines strength by allowing function of the distal element. In contrast, three proximal upstream elements necessary for basal and heat-regulated transcription have no requirement either for a TATA element or for any other proximal element. The behavior of promoters multiply mutant in these proximal elements implies that these elements function independently. We examined the interaction between the heat shock element (HSE) and the TATA element as the distance between the two factor-binding sites was increased. It was necessary to create a mutant HSE with an extended consensus sequence in order for the HSE to function at a distance. Moving this extended HSE 500 bases upstream did not increase its dependence on the TATA element, suggesting that the TATA independence of this element is intrinsic to its function and is not determined by distance from the promoter.
我们通过突变方法对人热休克蛋白70（hsp70）启动子的TATA元件与其他序列元件之间的相互作用进行了表征。在人细胞系中，该启动子远端元件的表达需要完整的TATA元件。hsp70的TATA元件在功能上可被猴病毒40早期启动子和腺病毒EIIa启动子的TATA元件所取代，以实现这种相互作用。因此，该启动子中的TATA元件既决定了合适的起始位点，又通过允许远端元件发挥功能来决定启动子强度。相比之下，基础转录和热调节转录所需的三个近端上游元件对TATA元件或任何其他近端元件均无需求。在这些近端元件中多重突变的启动子的行为表明这些元件独立发挥作用。随着热休克元件（HSE）与TATA元件之间两个因子结合位点的距离增加，我们研究了它们之间的相互作用。为了使HSE在一定距离处发挥功能，有必要创建一个具有扩展共有序列的突变型HSE。将这个扩展的HSE向上游移动500个碱基并不会增加其对TATA元件的依赖性，这表明该元件对TATA元件的独立性是其功能所固有的，并非由与启动子的距离所决定。
