Zeng J J, Hu W H, Hu X H, Tao H M, Zhong L, Liu L L
School of Life Sciences, Jinggangshan University, 343009 Ji'an, China.
Photosynthetica. 2022 Mar 31;60(2):271-279. doi: 10.32615/ps.2022.019. eCollection 2022.
The aim of this study was to explore how the mitochondrial alternative oxidase (AOX) pathway alleviates photoinhibition in chilled tomato () seedlings. Chilling induced photoinhibition in tomato seedlings despite the increases in thermal energy dissipation and cyclic electron flow around PSI (CEF-PSI). Chilling inhibited the function of PSII and blocked electron transport at the PSII acceptor side, however, it did not affect the oxygen-evolving complex on the donor side of PSII. Upregulation of the AOX pathway protects against photoinhibition by improving PSII function and photosynthetic electron transport in tomato seedlings under chilling stress. The AOX pathway maintained the open state of PSII and the stability of the entire photosynthetic electron transport chain. Moreover, the protective role of the AOX pathway on PSII was more important than that on PSI. However, inhibition of the AOX pathway could be compensated by increasing CEF-PSI activity under chilling stress.
本研究的目的是探究线粒体交替氧化酶（AOX）途径如何减轻低温胁迫下番茄幼苗的光抑制。尽管热能耗散增加以及围绕光系统I（CEF-PSI）的循环电子流增加，但低温仍诱导番茄幼苗发生光抑制。低温抑制了光系统II的功能，并在光系统II受体侧阻断了电子传递，然而，它并未影响光系统II供体侧的放氧复合体。AOX途径的上调通过改善低温胁迫下番茄幼苗的光系统II功能和光合电子传递来抵御光抑制。AOX途径维持了光系统II的开放状态以及整个光合电子传递链的稳定性。此外，AOX途径对光系统II的保护作用比对光系统I的更重要。然而，在低温胁迫下，AOX途径的抑制可通过增加CEF-PSI活性来补偿。
