In plants and algae, PGR5-dependent cyclic electron flow (CEF) is an important regulator of acclimation to fluctuating environments, but how PGR5 participates in CEF is unclear. In this work, we analyzed two PGR5s in cucumber (Cucumis sativus L.) under different conditions and found that CsPGR5a played the dominant role in PGR5-dependent CEF. The results of yeast two-hybrid, biomolecular fluorescence complementation (BiFC), blue native PAGE, and coimmunoprecipitation (CoIP) assays showed that PGR5a interacted with PetC, Lhcb3, and PsaH. Furthermore, the intensity of the interactions was dynamic during state transitions, and the abundance of PGR5 attached to cyt b6f decreased during the transition from state 1 to state 2, which revealed that the function of PGR5a is related to the state transition. We proposed that PGR5 is a small mobile protein that functions when attached to protein complexes.Two PGR5s are present in some species of algae and higher plants, and CsPGR5a plays the dominant role in PGR5-dependent cyclic electron flow in cucumber. PGR5 is a small and mobile protein that functions when attached to protein complexes. In this study, the function of PGR5 was found to be partially related to the state transition.

中文翻译：

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关键的循环电子流蛋白 PGR5 与细胞色素 b6f 结合，其功能部分受 LHCII 状态转换的影响

在植物和藻类中，依赖 PGR5 的循环电子流 (CEF) 是适应波动环境的重要调节因子，但 PGR5 如何参与 CEF 尚不清楚。在这项工作中，我们分析了黄瓜中的两个 PGR5 (黄瓜L.) 在不同条件下发现 CsPGR5a 在 PGR5 依赖的 CEF 中起主导作用。酵母双杂交、生物分子荧光互补 (BiFC)、蓝色天然 PAGE 和免疫共沉淀 (CoIP) 测定的结果表明 PGR5a 与 PetC、Lhcb3 和 PsaH 相互作用。此外，在状态转换过程中，相互作用的强度是动态的，并且大量的 PGR5 附着在 cytb6F在从状态 1 到状态 2 的转换过程中下降，这表明 PGR5a 的功能与状态转换有关。我们提出PGR5是一种小的移动蛋白，当附着于蛋白质复合物时发挥作用。在某些藻类和高等植物中存在两种PGR5，CsPGR5a在黄瓜中PGR5依赖的循环电子流动中起主导作用。PGR5 是一种小型且可移动的蛋白质，当附着于蛋白质复合物时会起作用。在这项研究中，发现 PGR5 的功能与状态转换部分相关。