一种可能源自绿藻的塑体,在Apicomplexan寄生虫中存在
S Köhler1, C F Delwiche, P W Denny
1Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
概括
像引起毒素形成症的寄生虫Apicomplexa一样,它们具有含有DNA的独特细胞器. 遗传学分析表明,这种有机体起源于绿色藻类,通过二级内共生.
科学领域:
- 寄生虫学的寄生虫学
- 分子生物学分子生物学
- 进化生物学 进化生物学
背景情况:
- 虫群是原生动物寄生虫,具有核和线粒体基因组.
- 他们还拥有独特的35基基圆形染色体外DNA.
研究的目的:
- 调查Apicomplexa中35基基基基因组外染色体DNA的起源和性质.
- 为了确定这个遗传元素的进化关系.
主要方法:
- 在现场杂交以定位Toxoplasma gondii中的35基基基因组DNA.
- 从Apicomplexa和其他生物体中获得的tuffa基因的家族遗传学分析.
主要成果:
- 35千基基因的DNA被定位到Toxoplasma gondii中的一个四膜结合的有机体.
- 遗传学分析将这种有机细胞基因组与蓝藻和塑性菌组合在一起,特别是与绿藻塑性菌组合在一起.
结论:
- 阿皮科普莱克萨通过二级内共生获得了塑体.
- 塑可能是从绿藻中获得的,这表明这些寄生虫的进化事件很重要.
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