一种分泌的氨酸-氨酸激酶决定了真核病原体Toxoplasma gondii的毒性
1Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO 63130, USA.
Science (New York, N.Y.)
|December 16, 2006
概括
毒淋病病毒性是由ROP18基因控制的. 这种在入侵期间分泌的氨酸-氨酸激酶显著增加了寄生虫的生长和宿主死亡率,突出显示了效应体分泌作为一种关键的毒性因素.
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 遗传学 是一个
背景情况:
- 毒淋巴菌在不同菌株之间表现出显著的毒性变异,尽管它们具有很高的遗传相似性.
- 了解T. gondii病毒性的遗传基础对于控制毒素菌至关重要.
研究的目的:
- 确定对I型Toxoplasma gondii菌株的极度毒性负责的遗传因素.
- 阐明特定基因和效应蛋白在寄生虫毒性中的作用.
主要方法:
- 基因映射被用来识别寄生虫染色体VIIa.上与毒性相关的定量特征位置.
- 定位克隆被用来识别候选病毒性基因 ROP18.
- 评估了ROP18的激酶活性和分泌,并通过转感染实验评估了它对寄生虫生长和宿主死亡率的影响.
主要成果:
- 染色体VIIa上的两个相邻的定量特征位置与I型血统毒性有关.
- 氨酸-氨酸激酶 ROP18 被确定为一个关键的毒性基因,多态,并分泌到宿主细胞中.
- 病毒性ROP18等位基因转化为III型菌株显著增加了寄生虫的生长和宿主死亡率 (4-5日志).
- 与ROP18的毒性相关的属性取决于其酶活性.
结论:
- ROP18是Toxoplasma gondii毒性的一个主要决定因素.
- 效应蛋白的分泌,如 ROP18,是导致寄生虫毒性的关键机制.
- 由于其在增强寄生虫生长和宿主死亡率方面的作用,ROP18激酶活性至关重要.
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