A mechanistic view of the reduction in photosynthetic protein abundance under diurnal light fluctuation
A mechanistic view of the reduction in photosynthetic protein abundance under diurnal light fluctuation
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昼夜光波动下光合蛋白质丰度减少的机制观点
DOI：
10.1093/jxb/erz164
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发表时间：
2019
影响因子：
6.9
通讯作者：
Chen T-W
中科院分区：
文献类型：
--
作者：
Pao Y-C;Stützel H;Chen T-W
为了模拟昼夜光波动的影响，我们首先将Pao等人（2019）模型中的参数转换为小时基础，假设在黑暗中12小时的光周期和零蛋白质合成。然后，使用三种FL模式（图1B）和DPI在1和60 mol m−2 d−1之间的SQ作为光输入，模拟Rubisco、电子传递和光收获蛋白的丰富度（Pao et al., 2019），然后将其分别转换为最大Rubisco羧化率（Vcmax）、Jmax和叶片PAR吸收率。根据Buckley et al.(2013)，使用常数将每个功能蛋白池中的氮量转换为相应的容量。在与Vialet-Chabrand et al.（2017）的FL实验相似的自然日光波动（FLN见图1B）和光强（DPI= 10和20 mol PAR m−2 d−1）下，该模型预测了FL对光合参数的影响：Vcmax和Jmax降低了21-22%（图1B）。1C， D)，叶片PAR吸收率降低2-4%（图2）。1 e)。这一预测在叶片PAR吸收（3-5%）的范围内，但与拟南芥中Vcmax（8-10%）和Jmax（11-15%）的预测不同（Vialet-Chabrand et al., 2017）。这些差异可能是由于模拟中假设在黑暗中缺乏蛋白质合成（见下文），或者由于他们的模型是用温室黄瓜（Cucumis sativus）参数化的，这可能与拟南芥有不同的PPSR-PAR响应。然而，实验和模型研究都表明，Vcmax和Jmax受FL的影响大于叶片PAR吸收。这可以通过以下事实来解释：光收集蛋白的合成速率在低于Rubisco和电子传递蛋白的PAR水平下达到饱和（图1A）。因此，在高DPI条件下，FL对光收获蛋白的影响几乎可以忽略不计。光照对Vcmax、Jmax和叶片吸收率的不同影响（图1C-E）表明，PPSR-PAR曲线的特性决定了光照波动对光合蛋白丰度的影响。因此，我们进一步研究了PPSR-PAR曲线参数、最大蛋白质合成速率（Smm，等于0.1、0.5或2.5）和曲率（kI，等于0.5或5）在DPI水平为1至60 mol m−2 d−1、氮供应水平（2 - 10 mM）和叶片的自然昼夜光波动（FLN，如图1B所示）下对光合驯化的影响程度
To simulate the effect of the diurnal light fluctuation, we first converted the parameters in the model of Pao et al.(2019) to an hourly basis by assuming a 12 h photoperiod and zero protein synthesis in the dark. Then, three FL patterns (Fig. 1B) and SQ with DPI between 1 and 60 mol m− 2 d− 1 were used as light input to simulate the abundance of Rubisco, electron transport, and light harvesting proteins (Pao et al., 2019), which were then converted to maximal Rubisco carboxylation rate (Vcmax), Jmax, and leaf PAR absorptance, respectively. Constants converting the amount of nitrogen in each functional protein pool into the corresponding capacities are used according to Buckley et al.(2013). Under natural diurnal light fluctuation (FLN in Fig. 1B) and light intensity (DPI= 10 and 20 mol PAR m− 2 d− 1) similar to the FL experiment in Vialet-Chabrand et al.(2017), the model predicted the effects of FL on photosynthetic parameters: Vcmax and Jmax were reduced by 21–22%(Fig. 1C, D) and leaf PAR absorptance by 2–4%(Fig. 1E). This prediction is within the range reported for leaf PAR absorptance (3–5%) but is different from that for the Vcmax (8–10%) and Jmax (11–15%) found in Arabidopsis (Vialet-Chabrand et al., 2017). These differences could be due to the lack of protein synthesis in the dark assumed in the simulations (see below) or due to the fact that their model was parameterized using greenhouse cucumber (Cucumis sativus), which might have different PPSR–PAR responses from Arabidopsis. However, both experimental and model studies suggest that Vcmax and Jmax were more affected by FL than leaf PAR absorptance. This can be explained by the fact that the synthesis rate of light harvesting proteins reaches saturation at a lower PAR level than Rubisco and electron transport proteins (Fig. 1A). Therefore, the effects of FL on light harvesting proteins under high DPI were almost negligible.The different effects of FL on Vcmax, Jmax, and leaf absorptance (Fig. 1C–E) imply that the characteristics of the PPSR–PAR curve determine the impact of light fluctuation on the abundance of photosynthetic proteins. Hence, we further examined the extent to which the PPSR–PAR curve parameters, the maximum protein synthesis rate (Smm, equal to 0.1, 0.5, or 2.5) and the curvature (kI, equal to 0.5 or 5), affect the photosynthetic acclimation under natural diurnal light fluctuation (FLN in Fig. 1B) with DPI levels between 1 and 60 mol m− 2 d− 1 in combinations with nitrogen supply levels (2–10 mM) and leaf
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影响因子：
6.9
作者：
Retkute R;Smith-Unna SE;Smith RW;Burgess AJ;Jensen OE;Johnson GN;Preston SP;Murchie EH
通讯作者：
Murchie EH
影响因子：
6.9
作者：
Annunziata MG;Apelt F;Carillo P;Krause U;Feil R;Koehl K;Lunn JE;Stitt M
通讯作者：
Stitt M
影响因子：
6.9
作者：
Pao YC;Chen TW;Moualeu-Ngangue DP;Stützel H
通讯作者：
Stützel H
影响因子：
5.2
作者：
SIMS, DA;PEARCY, RW
通讯作者：
PEARCY, RW
影响因子：
6.9
作者：
Matsubara S
通讯作者：
Matsubara S