不稳定的DNA放大在甲状腺素耐药的莱什马尼亚包括染色体外的圆圈,在稳定过程中重新定位
Cell
|September 1, 1984
概括
耐甲的热带莱什马尼亚表现出DNA放大,形成不稳定的圆形DNA,在药物选择下稳定成染色体数组. 这个过程反映了哺乳动物细胞中看到的基因放大.
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:
- 热带莱什马尼亚菌对一种关键的抗寄生虫药物甲索特酸产生耐药性.
- 原生动物的耐药性通常与遗传变化有关,包括DNA放大.
研究的目的:
- 为了研究莱什马尼亚热带菌 (Leishmania tropica) 中的甲醇耐药性的分子机制.
- 描述放大DNA区域的性质和稳定性.
主要方法:
- 在越来越高的甲状腺素度中培养热带莱什马尼亚.
- 使用CsCl-乙化密度梯度离心分析放大DNA.
- 描述放大DNA序列及其染色体关联.
主要成果:
- 在耐药的Leishmania tropica中发现了两个不同的放大DNA区域.
- 一个放大区域编码了双功能的乙基甲酸合成酶-二基甲酸减少酶 (TS-DHFR).
- 扩增DNA最初存在于不稳定的染色体外圆形形式,在长时间的药物选择下过渡到稳定的染色体数组.
结论:
- 这项研究阐明了Leishmania tropica.中的基因扩增的分子基础.
- 这些发现揭示了Leishmania和哺乳动物细胞中的基因放大机制之间的平行.
- 放大DNA的稳定染色体整合赋予了持续的耐药性.
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