Promoter-proximal tethering elements regulate enhancer-promoter specificity in the Drosophila Antennapedia complex
Promoter-proximal tethering elements regulate enhancer-promoter specificity in the Drosophila Antennapedia complex
复制标题
DOI：
10.1073/pnas.142291299
复制
发表时间：
2002-07-09
影响因子：
11.1
通讯作者：
Levine, M
中科院分区：
文献类型：
--
作者：
Calhoun, VC;Stathopoulos, A;Levine, M
绝缘子dna和启动子竞争调节复杂遗传位点内的增强子-启动子相互作用。在这里，我们为第三种机制提供了证据：启动子-近端系住元件。Antennapedia基因复合体的Scr-ftz区域包括两个已知的增强子，AE1和T1。AE1选择性地与ftz启动子相互作用，在原肠形成和种带伸长期间维持ftz表达的成对规则条纹。T1增强子位于ftz基因的3‘和Scr启动子的约25 kb 5’处，选择性地激活前胸和后头段的Scr表达。在转基因胚胎中检测了多种P元素的小基因，以确定AE1-ftz和T1-Scr特异性相互作用的基础。位于Scr转录起始位点5‘处约100 bp的450-bp DNA片段对于T1-Scr相互作用至关重要，并且当位于ftz启动子5’处时，可以介导ftz/lacZ报告基因的远程激活。我们认为Scr450片段包含有选择性地将T1招募到Scr启动子的系聚元件。栓系元件可能调节其他复杂遗传位点上的增强子-启动子相互作用。
insulator DNAs and promoter competition regulate enhancer-promoter interactions within complex genetic loci. Here we provide evidence for a third mechanism: promoter-proximal tethering elements. The Scr-ftz region of the Antennapedia gene complex includes two known enhancers, AE1 and T1. AE1 selectively interacts with the ftz promoter to maintain pair-rule stripes of ftz expression during gastrulation and germ-band elongation. The T1 enhancer, located 3' of the ftz gene and approximate to25 kb 5' of the Scr promoter, selectively activates Scr expression in the prothorax and posterior head segments. A variety of P element minigenes were examined in transgenic embryos to determine the basis for specific AE1-ftz and T1-Scr interactions. A 450-bp DNA fragment located approximate to100 bp 5' of the Scr transcription start site is essential for T1-Scr interactions and can mediate long-range activation of a ftz/lacZ reporter gene when placed 5' of the ftz promoter. We suggest that the Scr450 fragment contains tethering elements that selectively recruit T1 to the Scr promoter. Tethering elements might regulate enhancer-promoter interactions at other complex genetic loci.