一个发育调节的位置效应在Trypanosoma brucei的端粒位点
1Laboratory of Molecular Parasitology, Rockefeller University, New York, New York 10021-6399, USA.
Cell
|November 17, 1995
概括
虫杆菌通过切换变种特定的表面糖蛋白 (vsg) 基因来使用抗原变异. 这项研究揭示了端粒位置和发育阶段如何调节这种寄生虫的vsg基因转录.
科学领域:
- 寄生虫学的寄生虫学
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
背景情况:
- 虫杆菌通过抗原变异逃避宿主免疫系统.
- 这种变异是由不同的变异特异性表面糖蛋白 (vsg) 基因的表达介导的.
- 调节vsg基因转录,特别是在昆虫阶段,仍然不太了解.
研究的目的:
- 研究控制Trypanosoma brucei中vsg基因转录的机制.
- 确定位置位置和发育阶段在调节肌肉表达中的作用.
- 阐明管理促销者特定转录抑制的原则.
主要方法:
- 在不同促进体的控制下,将记者基因插入血流形式细胞中的端粒-近端部位.
- 在血流和前循环 (昆虫中肠) 阶段对转录活动的分析.
- 评估观察到的位置效应的稳定性和遗传性.
主要成果:
- 记者基因转录被抑制,当插入静音端粒-近端部位在血流形式的细胞,证明一个稳定和遗传的位置效应.
- 只有表达部位 (ES) 促进体在前循环细胞中表现出抑制,这表明了发育阶段特定的调节.
- 非ES促进体在前循环细胞中没有被抑制,突出显示了促进体的特异性.
结论:
- 端粒位置和发育阶段是Trypanosoma brucei中vsg基因转录的关键调节者.
- 观察到的位置效应和促进体特异性调节可能反映了在寄生虫生命周期中控制vsg基因表达的机制.
- 这些发现为管理抗原变异的复杂监管网络提供了洞察力.
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