Regulation of the human globin gene switching mechanisum based on unusual DNA structure

基于异常DNA结构的人类珠蛋白基因转换机制的调控

• 批准号: 08680749
• 负责人: WADA-KIYAMA Yuko
• 金额: $ 1.66万
• 依托单位: Nippon Medical School
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08680749/
• 关键词: The human globin gene; Unusual structure DNA; bent DNA; Nucleosomal phasing; Transcriptional regulation

The human beta-globin locus contains five active genes (s-, Gy-, Ay-, S-and beta-globins) and a j3-globin pseudogene (PSIbeta-globin) in a region larger than 70 kb. The sequence homologies between these genes were mostly lost and insertions of AIu and Li repetitive sequences have occurred since their separation, resulting in a total mixture of the nucleotide sequence. However, these genes show marked coordination when they switch expression during development and differentiation. This requires strict control of the transcription machinery including RNA polymerases and the interaction between the promoters located as far as 42 kb. The locus control region that governs this coordination is located 6 kb to more than 20 kb upstream of the e-globin gene. Therefore, the regulation of expression of these genes provides a good model in which to study the biological significance of unusual DNA structure in genomic DNA.Periodicity of DNA bend sites was firstly reported in the human epsilon-globin gene region (J.Biol. Chem. 269.1994) and subsequently in other regions of the same locus. Based on the results, we proposed that periodic bent DNA are associated with Long range coordinations of genomic DNA.In this study we mapped a total of 98 bend sites in the about 70 kb region of the beta-globin locus by circular permutation assay with average interval of approximately 680 bp between them. Most of their locations relative to the cap sites were conserved during evolution. There were the 75 potentialbend core sequences A/A/A (A2N8A2N8A2) found in the 51 bend sites, 64 sequences from 48 sites showed bending profiles by oligonucleotide-based assay. These lines of evidence suggested that DNA bending is a basic and universal structural component of genomic DNA and has a direct or indirect influence on biological phenomena such as regulation of the golobin gene switching mechanism.

人β-珠蛋白基因座在大于70 kb的区域中含有5个活性基因（s-、戈伊-、Ay-、S-和β-珠蛋白）和β 3-珠蛋白假基因（PS1 β-珠蛋白）。这些基因之间的序列同源性大部分丢失，并且自从它们分离以来已经发生了AIu和Li重复序列的插入，导致核苷酸序列的完全混合。然而，这些基因在发育和分化过程中切换表达时表现出明显的协调性。这需要严格控制转录机制，包括RNA聚合酶和位于远至42 kb的启动子之间的相互作用。控制这种协调的基因座控制区位于e-珠蛋白基因上游6 kb至20 kb以上。DNA弯曲位点的周期性首先在人ε-珠蛋白基因区域中报道（J. Biol. Chem. 269. 1994），随后在同一基因座的其它区域中报道。在此基础上，我们提出了周期性弯曲的DNA与基因组DNA的长程配位有关，在本研究中，我们利用环状排列分析法在β-珠蛋白基因座的约70 kb区域内共定位了98个弯曲位点，它们之间的平均间隔约为680 bp。它们相对于帽位点的大多数位置在进化过程中是保守的。在51个弯曲位点中发现了75个潜在的弯曲核心序列A/A/A（A2 N8 A2），其中48个位点的64个序列显示出弯曲特征。这些证据表明，DNA弯曲是基因组DNA的基本和普遍的结构组成部分，并直接或间接地影响生物现象，如调节golobin基因开关机制。

项目成果

木山裕子: "An intrachromosomal repeating unit based on DNA bending of the human β-globin gene locus." Blood (Abstract). 86. 7a- (1995)

Yuko Kiyama：“基于人类 β-珠蛋白基因座 DNA 弯曲的染色体内重复单元。”（摘要）86. 7a- (1995)。

Y.Wada-Kiyama: "Conservation and periodicity of DNAbendsites in the human beta-globin gene locus." J.Biol.Chem.270 (21). 12439-12445 (1995)

Y.Wada-Kiyama：“人类 β-珠蛋白基因座中 DNA 弯曲位点的保守性和周期性。”

木山 裕子: "A structural basis for DNase I-hypersensitive sites in the human β-globin locus control region" Blood(Abstract). 88. 148a (1996)

Yuko Kiyama：“人类 β-珠蛋白基因座控制区域中 DNase I 超敏位点的结构基础”Blood（摘要）88. 148a (1996)。

木山裕子: "Conservation and periodicity of DNA bend sites in the human β-globin gene locus" J.Biol.Chem.270(21). 12439-12445 (1995)

Yuko Kiyama：“人类 β-珠蛋白基因座中 DNA 弯曲位点的保守性和周期性”J.Biol.Chem.270(21) (1995)。

木山裕子: "Conservation and periodicity of DNA bend sites in eukaryotic genomes." DNA Res.3. 25-30 (1996)

Yuko Kiyama：“真核基因组中 DNA 弯曲位点的保守性和周期性。”25-30 (1996)。