Gaszner M, Vazquez J, Schedl P
Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544 USA.
Genes Dev. 1999 Aug 15;13(16):2098-107. doi: 10.1101/gad.13.16.2098.
The scs and scs' elements were proposed to function as chromatin domain boundaries for the 87A7 heat shock locus in Drosophila melanogaster. Here we report the identification and characterization of SBP (scs binding protein), a component of the scs nucleoprotein complex. SBP binds specifically to a 24-bp region of scs in vitro and is associated with scs in vivo. Multiple copies of an oligonucleotide containing the SBP recognition sequence are capable of blocking enhancer-promoter interactions in transgene assays. Mutations in the oligonucleotide that disrupt SBP binding in vitro also eliminate enhancer-blocking activity in vivo. We show that SBP is encoded by the zeste-white 5 gene and that mutations in zeste-white 5 reduce the enhancer-blocking activity of the multimerized oligonucleotides.
scs及其元件被认为在黑腹果蝇中作为87A7热休克基因座的染色质结构域边界发挥作用。在此我们报告了SBP（scs结合蛋白）的鉴定和特性，它是scs核蛋白复合体的一个组分。SBP在体外能特异性结合scs的一个24bp区域，且在体内与scs相关联。含有SBP识别序列的寡核苷酸的多个拷贝在转基因实验中能够阻断增强子-启动子相互作用。在体外破坏SBP结合的寡核苷酸中的突变在体内也消除了增强子阻断活性。我们表明SBP由zeste-white 5基因编码，且zeste-white 5中的突变降低了多聚化寡核苷酸的增强子阻断活性。
