人类的马环球蛋白基因在贝塔环球蛋白位点中独立于其他基因被静止
1National Institute for Medical Research, Mill Hill, London, UK.
Nature
|March 21, 1991
概括
位置控制区域 (LCR) 指导全球蛋白基因表达. 这项研究表明,在成年小鼠中,胎儿马环球蛋白基因沉默独立于β-环球蛋白竞争,这表明涉及特定阶段的因素.
科学领域:
- 遗传学 是一个遗传学.
- 分子生物学分子生物学
- 发展生物学 发展生物学
背景情况:
- 人类红色素形成涉及发育阶段特定的全球蛋白基因表达.
- 在epsilon基因上游的位置控制区域 (LCR) 指导高水平的全球蛋白基因表达.
- 假设beta-globin和gamma-globin基因之间对LCR相互作用的竞争会使成人胎儿的玛基因沉默.
研究的目的:
- 调查LCR和β-环球蛋白竞争在抑制人类A玛环球蛋白基因在发育过程中的作用.
- 为了确定单独的LCR是否足以调节整个红色素形成过程中的玛-环球蛋白基因表达.
主要方法:
- 携带与LCR相关的人类A马球蛋白基因的转基因小鼠的生成.
- 在红色素形成的胚胎和成人阶段对转基因表达模式的分析.
- 在存在和缺乏内源性β-全球蛋白竞争的情况下,对玛-全球蛋白基因表达的比较.
主要成果:
- 由LCR指导的A玛环球蛋白转基因在胚胎阶段显示出高水平的表达.
- 在成年动物中,尽管存在LCR,转基因被沉默了.
- 沉默发生不论从内源性β-环球蛋白基因的竞争.
结论:
- 这种LCR本质上不去调节马环球蛋白基因,允许发育性沉默.
- 从β-环球蛋白基因的竞争是不必要的沉默胎儿的玛基因在成年生活.
- 与侧面序列结合的特定阶段因子可能会调解马环球蛋白基因的沉默.
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