疟疾. 疟疾. 在各种基因中配合的沉声元件
K W Deitsch1, M S Calderwood, T E Wellems
1Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892-0425, USA.
Nature
|August 31, 2001
概括
疟疾寄生虫在DNA合成过程中使大多数基因沉默. 这种沉默依赖于控制区域之间的相互作用,这对于抗原变异至关重要.
科学领域:
- 分子生物学分子生物学
- 寄生虫学的寄生虫学
- 遗传学 是一个遗传学.
背景情况:
- 疟原虫 (Plasmodium falciparum) 引起疟疾,并且拥有大约50个不同的基因.
- 瓦尔基因编码蛋白质,调解受感染的红细胞的细胞粘附.
- 寄生虫一次只表达一个变异基因,使其他基因沉默以逃避免疫.
研究的目的:
- 研究Plasmodium falciparum中各种基因沉默的时间和机制.
- 识别参与调节不同基因表达的遗传元素.
- 阐明疟疾寄生虫抗原变异的过程.
主要方法:
- 细胞周期分析Plasmodium falciparum的细胞周期分析.
- 研究各种基因调控元素,包括5'-侧翼区域和内基因.
- 评估不同控制区域之间的合作互动.
主要成果:
- 瓦尔基因沉默是在寄生虫细胞周期的S阶段建立的.
- 沉默依赖于5'-侧翼区域和var基因的内核之间的合作相互作用.
- 特定的控制区域一起工作,以保持基因沉默.
结论:
- DNA 合成 (S 阶段) 是建立 var 基因沉默的关键窗口.
- 单独的监管元素之间的合作相互作用对于协调的多种基因沉默至关重要.
- 了解这些机制可以澄清疟疾寄生虫如何实现抗原变异.
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