来自T. brucei的抗原基因表达部位的基因和转录
Cell
|June 2, 1989
概括
研究人员克隆了T. brucei的AnTat 1.3A抗原基因表达部位,揭示了七个表达部位相关基因 (ESAGs) 和一个逆位子. ESAG 4显示了酵母腺酸环酶和跨膜蛋白质特征的同质性.
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:
- 在Trypanosoma brucei中的AnTat 1.3A抗原基因表达部位对于寄生虫的生存至关重要.
- 了解这种表达部位的组织和调节是开发新治疗策略的关键.
研究的目的:
- 在T. brucei. 中克隆和表征AnTat 1.3A抗原基因表达部位.
- 识别和分析表达场所内的假定编码区域 (ESAGs) 和其他元素.
主要方法:
- 基因组图书馆克隆了200 kb的表达性染色体.
- 序列分析以确定编码区域和逆位子.
- RNA聚合酶活性测定和α-amanitin敏感性测试.
- 紫外线照射以研究RNA处理和促进物映射.
主要成果:
- 克隆表达部位包含AnTat 1.3A抗原基因,七个表达部位关联基因 (ESAGs) 和一个RIME复原体.
- ESAG 4编码了一种同类于酵母腺酸环酶的多,具有跨膜蛋白特征.
- 表达部位在血流形式中被一个类似于pol I的聚合酶转录;相关序列由一个对α-amanitin敏感的聚合酶构成性地转录.
- 紫外线照射表明,转录促进体位于抗原基因上游大约45kb处.
结论:
- AnTat 1.3A抗原基因表达部位具有复杂的结构,包括具有潜在功能的多个ESAG.
- 通过不同的聚合酶进行差异转录表明T. brucei. 具有复杂的调节机制.
- 识别ESAG 4提供了对寄生虫潜在信号通路的见解.
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