叶绿体NADH脱酶类复杂介导的循环电子流是C4捆盖细胞中的主要电子输送路径
Maria Ermakova1,2, Russell Woodford1,2, Duncan Fitzpatrick1
1Division of Plant Science, Centre of Excellence for Translational Photosynthesis, Research School of Biology, Australian National University, Acton, ACT, 2600, Australia.
The New phytologist
|July 22, 2024
概括
由质体中介的循环电子流 (CEF) NADH脱酶样复合体 (NDH) 对于C4植物的生产力至关重要. 这一过程主要发生在捆束细胞中,为碳固定提供必要的ATP.
科学领域:
- 植物生理学 植物生理学
- 光合作用研究研究 光合作用研究
- 分子生物学分子生物学
背景情况:
- 由于二氧化碳缩机制,C4植物表现出卓越的生产力,其中涉及中和束细胞,需要ATP.
- 已知质体NADH脱酶样复合体 (NDH) 在C4光合作用周期电子流 (CEF) 中的作用,但其对电子流的细胞特异性贡献尚不清楚.
研究的目的:
- 调查CEF和NDH对C4植物中细胞水平电子流量的贡献.
- 量化通过NDH的电子流量,在Setaria viridis的捆束 (BS) 和半细胞中.
主要方法:
- 基因编辑的Setaria viridis缺乏功能性NDH (无ndhO等位基因) 的发展.
- 建立方法来量化在BS和中细胞中通过NDH的电子流.
主要成果:
- 在BS细胞中,CEF占光系统I (PSI) 减少电子的84%,主要通过NDH.
- 在中粒细胞中,NDH对电子运输的贡献是最小的.
- 缺乏NDH的植物表现出减少的二氧化碳吸收和生长,而这无法通过增加的二氧化碳来补偿.
结论:
- 通过NDH介导的CEF是BS质体中的主要电子运输通路.
- 在C4植物的BS细胞中,NDH在产生C3循环的ATP中起着至关重要的作用.
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