Xiang Ping, Fang Xiangdong, Yin Wenxuan, Barkess Grainne, Li Qiliang
Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA 98195, USA.
Biochem Biophys Res Commun. 2006 Jun 2;344(2):623-30. doi: 10.1016/j.bbrc.2006.03.189. Epub 2006 Apr 6.
Non-coding exons of epsilon-globin mRNA originating within the 236 kb upstream region of the epsilon-globin gene were identified in human primary tissues and K562 cells. One predominant type of upstream epsilon mRNA, which originated in the -76 kb region 5' to the epsilon gene, was present in human primary tissues, whereas 11 other isoforms were identified in K562 cells. Fragment from the -76 kb region possessed promoter activity and a prominent DNase I hypersensitive site was formed in the region approximately 2 kb 5' to the -76 kb promoter in human fetal liver, but not in K562 cells. The promoter activity in the -236 kb region resided in a retrotransposon in K562 cells. A DNase I hypersensitive site was formed at the -236 kb promoter in K562 cells, but not in human fetal liver. We discussed these results in the context of intergenic transcription and chromatin opening in the beta-globin gene cluster.
在人类原代组织和K562细胞中鉴定出源自ε-珠蛋白基因上游236 kb区域内的ε-珠蛋白mRNA的非编码外显子。一种主要类型的上游ε mRNA起源于ε基因5'端的-76 kb区域，存在于人类原代组织中，而在K562细胞中鉴定出了其他11种异构体。来自-76 kb区域的片段具有启动子活性，在人类胎儿肝脏中，在-76 kb启动子5'端约2 kb的区域形成了一个明显的DNase I超敏位点，但在K562细胞中未形成。-236 kb区域的启动子活性存在于K562细胞中的一个逆转录转座子中。在K562细胞的-236 kb启动子处形成了一个DNase I超敏位点，但在人类胎儿肝脏中未形成。我们在β-珠蛋白基因簇的基因间转录和染色质开放的背景下讨论了这些结果。
