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在Archaeplastida中,线粒体细胞染色体c成熟系统的反复演化开关
Huang Li1, Soujanya Akella1,2, Carina Engstler3
1Center for Plant Science Innovation, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA.
Nature communications
|February 20, 2024
概括
科学家们发现,Archaeplastida反复演变为线粒体细胞染色体c成熟 (CCM) 的新途径. 这种从系统I向系统III (全细胞染色体c合成酶) 的转变会影响藻类的生长和呼吸.
科学领域:
- 进化生物学 进化生物学
- 分子生物学分子生物学
- 生物化学 生物化学
背景情况:
- 线粒体细胞染色体成熟 (CCM) 是必不可少的,通过两个主要途径发生:系统I和系统III.
- 这些CCM系统在Archaeplastida的分布是马赛克式的,这促使人们对推动它们重复发展的进化机制进行调查.
研究的目的:
- 研究Archaeplastida中CCM通路的反复演变背后的遗传机制和进化力量.
- 确定Archaeplastida CCM中真核细胞特异性全细胞染色体c合成酶 (HCCS) 的功能作用.
主要方法:
- 对比基因组分析以确定Archaeplastida中的CCM系统分布.
- 功能补充测试使用酵母和Arabidopsis突变体来测试HCCS活性.
- 藻类HCCS突变体的表型分析,包括生长,呼吸和代谢概况.
主要成果:
- 从祖先系统I到系统III (HCCS) 的反复演化转变在11个古类细胞系中被观察到.
- 阿基普拉斯蒂德HCCS成功地拯救了酵母系统III和阿拉比多普西斯系统I突变物,证明了功能性保护.
- 藻类HCCS突变体表现出生长受损,呼吸减弱和代谢状况改变,表明缺乏CCM.
结论:
- 考古细胞原体HCCS同类物作为系统III的组件,独立于系统I运行.
- 这项研究阐明了Archaeplastida中CCM通路的进化轨迹和功能分歧.
- 研究结果提供了关于生物途径的重复选择及其进化后果的见解.
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