Ratnitsyna Daria, Yudina Lyubov, Sukhova Ekaterina, Sukhov Vladimir
Department of Biophysics, N. I. Lobachevsky State University of Nizhny Novgorod, 603950 Nizhny Novgorod, Russia.
Plants (Basel). 2023 Sep 8;12(18):3211. doi: 10.3390/plants12183211.
Photodamage of photosynthetic electron transport is a key mechanism of disruption of photosynthesis in plants under action of stressors. This means that investigation of photodamage is an important task for basic and applied investigations. However, its complex mechanisms restrict using experimental methods of investigation for this process; the development of mathematical models of photodamage and model-based analysis can be used for overcoming these restrictions. In the current work, we developed the modified Farquhar-von Caemmerer-Berry model which describes photodamage of photosynthetic electron transport in C plants. This model was parameterized on the basis of experimental results (using an example of pea plants). Analysis of the model showed that combined inactivation of linear electron flow and Rubisco could induce both increasing and decreasing photodamage at different magnitudes of inactivation of these processes. Simulation of photodamage under different temperatures and light intensities showed that simulated temperature dependences could be multi-phase; particularly, paradoxical increases in the thermal tolerance of photosynthetic electron transport could be observed under high temperatures (37-42 °C). Finally, it was shown that changes in temperature optimums of linear electron flow and Rubisco could modify temperature dependences of the final activity of photosynthetic electron transport under photodamage induction; however, these changes mainly stimulated its photodamage. Thus, our work provides a new theoretical tool for investigation of photodamage of photosynthetic processes in C plants and shows that this photodamage can be intricately dependent on parameters of changes in activities of linear electron flow and Rubisco including changes induced by temperature.
光合电子传递的光损伤是植物在应激源作用下光合作用破坏的关键机制。这意味着光损伤的研究是基础研究和应用研究的一项重要任务。然而，其复杂的机制限制了对该过程采用实验研究方法；光损伤数学模型的开发和基于模型的分析可用于克服这些限制。在当前工作中，我们开发了改进的Farquhar-von Caemmerer-Berry模型，该模型描述了C植物光合电子传递的光损伤。该模型基于实验结果（以豌豆植株为例）进行了参数化。对模型的分析表明，线性电子流和Rubisco的联合失活在这些过程不同程度的失活情况下，既能诱导光损伤增加，也能诱导光损伤减少。在不同温度和光照强度下对光损伤的模拟表明，模拟的温度依赖性可能是多阶段的；特别是，在高温（37 - 42°C）下可观察到光合电子传递的热耐受性出现反常增加。最后，结果表明，线性电子流和Rubisco的温度最适值变化可改变光损伤诱导下光合电子传递最终活性的温度依赖性；然而，这些变化主要是刺激了其光损伤。因此，我们的工作为研究C植物光合过程的光损伤提供了一种新的理论工具，并表明这种光损伤可能复杂地依赖于线性电子流和Rubisco活性变化的参数，包括温度诱导的变化。
