Hübner Katrin, Phi-van Loc
Institute of Animal Welfare and Animal Husbandry, Dörnbergstr. 25-27, 29223 Celle, Germany.
Biochim Biophys Acta. 2010 May-Jun;1799(5-6):442-7. doi: 10.1016/j.bbagrm.2010.02.001. Epub 2010 Feb 11.
The 5'-flanking region of the chicken glioma-amplified sequence (GAS) 41 gene is close to the 3' end of the lysozyme gene and contains no typical TATA box, but several GC boxes. In this study, we have localized the GAS 41 promoter to this narrow region. Electrophoretic mobility shift assays and chromatin immunoprecipitation analyses revealed that Sp1 and Sp3 bind to this promoter. Mapping by a technique of indirect end labeling demonstrated that the Sp1-binding sites contained in this region exactly co-map with two previously identified DNase I hypersensitive (HS) sites, which suggests the important role of Sp1 binding in maintaining an open chromatin structure of the GAS41 promoter. We further found that Sp1 and Sp3 strongly activate CAT expression controlled by the putative GAS41 promoter in Drosophila Schneider S2 cells and that deletion of the Sp1 sites resulted in a loss of promoter activity in chicken HD11 cells. The results indicate that transcription factors of the Sp family play an important role in the transcriptional regulation of the chicken GAS41 gene.
鸡神经胶质瘤扩增序列（GAS）41基因的5'侧翼区域靠近溶菌酶基因的3'末端，不含典型的TATA盒，但含有几个GC盒。在本研究中，我们已将GAS 41启动子定位到这个狭窄区域。电泳迁移率变动分析和染色质免疫沉淀分析表明，Sp1和Sp3与该启动子结合。通过间接末端标记技术进行的定位表明，该区域所含的Sp1结合位点与两个先前鉴定的DNase I超敏（HS）位点精确共定位，这表明Sp1结合在维持GAS41启动子的开放染色质结构中起重要作用。我们进一步发现，Sp1和Sp3在果蝇Schneider S2细胞中强烈激活由推定的GAS41启动子控制的CAT表达，并且Sp1位点的缺失导致鸡HD11细胞中启动子活性丧失。结果表明，Sp家族转录因子在鸡GAS41基因的转录调控中起重要作用。
