Genetic decrease in fatty acid unsaturation of phosphatidylglycerol increased photoinhibition of photosystem I at low temperature in tobacco leaves
Genetic decrease in fatty acid unsaturation of phosphatidylglycerol increased photoinhibition of photosystem I at low temperature in tobacco leaves
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DOI：
10.1016/j.bbabio.2012.03.010
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发表时间：
2012-08-01
影响因子：
4.3
通讯作者：
Murata, N.
中科院分区：
文献类型：
--
作者：
Ivanov, A. G.;Allakhverdiev, S. I.;Murata, N.
磷脂酰甘油（PG）中脂肪酸不饱和度水平降低的转基因烟草植物的叶片表现出比野生型植物略低的光系统I（PSI）反应中心P700（P700（+））的稳态氧化水平。野生型植物的PSI光化学仅受强光处理的轻微影响。令人惊讶的是，所有转基因株系的植物表现出比野生型植物高得多的PSI光抑制的敏感性。这伴随着P700（+）在黑暗中的再还原速率快2.5倍，表明高光处理的转基因叶片中PSI周围的循环电子流的能力更高。这与更高的系统间电子池大小相关，表明与野生型植物相比，PG不饱和度改变的烟草转基因株系中PQ池过度减少。本文讨论了PG不饱和度在低温光抑制条件下烟草PSI下调、PSI依赖的循环电子流能力调节和激发光能分配中的生理作用。这篇文章是特刊的一部分，题为：光合作用研究的可持续性：从自然到人工。(C)2012爱思唯尔有限公司版权所有。
Leaves of transgenic tobacco plants with decreased levels of fatty acid unsaturation in phosphatidylglycerol (PG) exhibited a slightly lower level of the steady state oxidation of the photosystem I (PSI) reaction center P700 (P700(+)) than wild-type plants. The PSI photochemistry of wild-type plants was only marginally affected by high light treatments. Surprisingly, all plants of transgenic lines exhibited much higher susceptibility to photoinhibition of PSI than wild-type plants. This was accompanied by a 2.5-fold faster re-reduction rate of P700(+) in the dark, indicating a higher capacity for cyclic electron flow around PSI in high light treated transgenic leaves. This was associated with a much higher intersystem electron pool size suggesting over-reduction of the PQ pool in tobacco transgenic lines with altered PG unsaturation compared to wild-type plants. The physiological role of PG unsaturation in PSI down-regulation and modulation of the capacity of PSI-dependent cyclic electron flows and distribution of excitation light energy in tobacco plants under photoinhibitory conditions at low temperatures is discussed. This article is part of a Special Issue entitled: Photosynthesis Research for Sustainability: from Natural to Artificial. (C) 2012 Elsevier B.V. All rights reserved.