Role of Thylakoid Protein Phosphorylation in Energy-Dependent Quenching of Chlorophyll Fluorescence in Rice Plants

Abstract

Under natural environments, light quality and quantity are extremely varied. To respond and acclimate to such changes, plants have developed a multiplicity of molecular regulatory mechanisms. Non-photochemical quenching of chlorophyll fluorescence (NPQ) and thylakoid protein phosphorylation are two mechanisms that protect vascular plants. To clarify the role of thylakoid protein phosphorylation in energy-dependent quenching of chlorophyll fluorescence (qE) in rice plants, we used a direct Western blot assay after BN-PAGE to detect all phosphoproteins by P-Thr antibody as well as by P-Lhcb1 and P-Lhcb2 antibodies. Isolated thylakoids in either the dark- or the light-adapted state from wild type (WT) and PsbS-KO rice plants were used for this approach to detect light-dependent interactions between PsbS, PSII, and LHCII proteins. We observed that the bands corresponding to the phosphorylated Lhcb1 and Lhcb2 as well as the other phosphorylated proteins were enhanced in the PsbS-KO mutant after illumination. The qE relaxation became slower in WT plants after 10 min HL treatment, which correlated with Lhcb1 and Lhcb2 protein phosphorylation in the LHCII trimers under the same experimental conditions. Thus, we concluded that light-induced phosphorylation of PSII core and Lhcb1/Lhcb2 proteins is enhanced in rice PsbS-KO plants which might be due to more reactive-oxygen-species production in this mutant.

Physiological and molecular mechanisms regulated mesophyll conductance under severe drought in water-saving drought-resistant rice

“…Therefore, the high photosynthetic production potential of WDR in severe drought would be fully understood by revealing the interaction mechanisms between g m and energy distribution in PSII and PSI system. Mesophyll cell structures including anatomical structure, ultrastructures of chloroplast and thylakoid membrane, and intracellular physiological traits such as aquaporins, carbonic anhydrase, and thylakoid membrane proteins and protein complexes have different functions and contribution pathways to regulate g m and energy distribution during responding to stress environment in rice plants (Flexas et al ., 2012; Xiong et al ., 2017; Wang et al ., 2018b; Pashayeva et al ., 2021; Wu et al ., 2021). However, it is still indistinct how the cell structures interacted with physiological functions regulate g m and energy distribution to maintaining high photosynthetic production ability in water stress in rice plants.…”

Integrative analyses of morphology, physiology, and transcriptional expression profiling reveal miRNAs involved in culm color in bamboo

“…Photosynthesis is pivotal for plant growth and yield (Yang et al, 2014 ), and gene encoding photosynthetic enzymes play significant roles in photosynthesis and pigmentation (Pashayeva et al, 2021 ; Li et al, 2022b ). The KEGG results showed that photosynthesis and photosynthesis-antenna proteins were significantly enriched ( Figure 3C ).…”

Harnessing Chlorophyll Fluorescence for Phenotyping Analysis of Wild and Cultivated Tomato for High Photochemical Efficiency under Water Deficit for Climate Change Resilience

“…In our experiment, the Fv/Fm ratio that was measured in dark-adapted (20 min) leaves was found to decrease under MoDS in all cultivars, but to remain unaffected in the introgression line IL12-4 which decreased only under SDS (Figure 4a). However, the use of Fv/Fm as an efficient indicator has been frequently questioned [25,[74][75][76], and recently it was recommended that the Fv/Fm parameter must not to be related to the efficiency of PSII photochemistry [77,78]. In contrast, the pattern of the redox state of quinone A (Q A ) has been shown to be a good indicator to probe photosynthetic efficiency and to determine the impact of abiotic or biotic stress on photosynthesis [25,43,79].…”