Fakultät für Biologie, Ludwig-Maximilians-Universität München, Grosshaderner Str. 2-4, 82152 Martinsried, Germany.
Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany.
Plant Physiol. 2024 Jan 31;194(2):982-1005. doi: 10.1093/plphys/kiad535.
During photosynthesis, plants must manage strong fluctuations in light availability on different time scales, leading to long-term acclimation and short-term responses. However, little is known about the regulation and coordination of these processes and the modulators involved. In this study, we used proteomics, metabolomics, and reverse genetics to investigate how different light environmental factors, such as intensity or variability, affect long-term and short-term acclimation responses of Arabidopsis (Arabidopsis thaliana) and the importance of the chloroplast redox network in their regulation. In the wild type, high light, but not fluctuating light, led to large quantitative changes in the proteome and metabolome, accompanied by increased photosynthetic dynamics and plant growth. This finding supports light intensity as a stronger driver for acclimation than variability. Deficiencies in NADPH-thioredoxin reductase C (NTRC) or thioredoxins m1/m2, but not thioredoxin f1, almost completely suppressed the re-engineering of the proteome and metabolome, with both the induction of proteins involved in stress and redox responses and the repression of those involved in cytosolic and plastid protein synthesis and translation being strongly attenuated. Moreover, the correlations of protein or metabolite levels with light intensity were severely disturbed, suggesting a general defect in the light-dependent acclimation response, resulting in impaired photosynthetic dynamics. These results indicate a previously unknown role of NTRC and thioredoxins m1/m2 in modulating light acclimation at proteome and metabolome levels to control dynamic light responses. NTRC, but not thioredoxins m1/m2 or f1, also improves short-term photosynthetic responses by balancing the Calvin-Benson cycle in fluctuating light.
在光合作用过程中，植物必须应对不同时间尺度上光照可用性的剧烈波动，从而导致长期的驯化和短期的响应。然而，对于这些过程的调控和协调以及涉及的调节剂知之甚少。在这项研究中，我们使用蛋白质组学、代谢组学和反向遗传学来研究不同的光环境因素（如强度或可变性）如何影响拟南芥（Arabidopsis thaliana）的长期和短期驯化响应，以及叶绿体氧化还原网络在其调控中的重要性。在野生型中，强光而不是波动的光会导致蛋白质组和代谢组发生大量的定量变化，伴随着光合作用动态和植物生长的增加。这一发现支持了光强度作为驯化更强的驱动因素，而不是可变性。NADPH-硫氧还蛋白还原酶 C（NTRC）或硫氧还蛋白 m1/m2的缺陷，但不是硫氧还蛋白 f1，几乎完全抑制了蛋白质组和代谢组的再工程，参与应激和氧化还原反应的蛋白质的诱导以及参与细胞质和质体蛋白合成和翻译的蛋白质的抑制都被强烈减弱。此外，蛋白质或代谢物水平与光强度的相关性严重紊乱，表明光依赖的驯化响应存在普遍缺陷，导致光合作用动态受损。这些结果表明 NTRC 和硫氧还蛋白 m1/m2 在调节蛋白质组和代谢组水平的光驯化方面发挥了以前未知的作用，以控制动态光响应。NTRC，但不是硫氧还蛋白 m1/m2 或 f1，也通过在波动的光中平衡卡尔文-本森循环来改善短期光合作用响应。
