A kinetic model of rapidly reversible nonphotochemical quenching
A kinetic model of rapidly reversible nonphotochemical quenching
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DOI：
10.1073/pnas.1211017109
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发表时间：
2012-08
期刊：
影响因子：
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通讯作者：
J. Zaks;K. Amarnath;D. Kramer;K. Niyogi;G. Fleming
中科院分区：
文献类型：
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作者：
J. Zaks;K. Amarnath;D. Kramer;K. Niyogi;G. Fleming
放氧光合生物具有非光化学猝灭（NPQ）途径，可防止光诱导的损伤。植物中的大多数NPQ在快速的时间尺度上通过类囊体腔的pH值的变化来调节。为了量化NPQ中快速可逆的成分（称为qE），我们开发了光系统II中叶绿素激发的pH依赖性猝灭的数学模型。我们的表达qE依赖于质子化的PsbS和紫黄质脱环氧酶的紫黄质的脱环氧化。该模型能够模拟qE在低和高光强度下的动力学。模拟表明，激活qE的管腔的pH值本身并不受qE的影响。我们的模型提供了一个框架，用于测试假设的QE机制，并评估QE在改善植物适应性中的作用。
Oxygen-evolving photosynthetic organisms possess nonphotochemical quenching (NPQ) pathways that protect against photo-induced damage. The majority of NPQ in plants is regulated on a rapid timescale by changes in the pH of the thylakoid lumen. In order to quantify the rapidly reversible component of NPQ, called qE, we developed a mathematical model of pH-dependent quenching of chlorophyll excitations in Photosystem II. Our expression for qE depends on the protonation of PsbS and the deepoxidation of violaxanthin by violaxanthin deepoxidase. The model is able to simulate the kinetics of qE at low and high light intensities. The simulations suggest that the pH of the lumen, which activates qE, is not itself affected by qE. Our model provides a framework for testing hypothesized qE mechanisms and for assessing the role of qE in improving plant fitness in variable light intensity.