Rising rates of starch degradation during daytime and trehalose 6-phosphate optimize carbon availability.
Rising rates of starch degradation during daytime and trehalose 6-phosphate optimize carbon availability.
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DOI：
10.1093/plphys/kiac162
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发表时间：
2022-08-01
期刊：
影响因子：
7.4
通讯作者：
Stitt, Mark
中科院分区：
文献类型：
--
作者：
Ishihara, Hirofumi;Alseekh, Saleh;Feil, Regina;Perera, Pumi;George, Gavin M.;Niedzwiecki, Piotr;Arrivault, Stephanie;Zeeman, Samuel C.;Fernie, Alisdair R.;Lunn, John E.;Smith, Alison M.;Stitt, Mark
许多植物，包括拟南芥（Arabidopsis thaliana），在光照下积累淀粉，并在夜间重新调动淀粉以支持维持和生长。淀粉的合成和降解通常被视为时间上独立的过程。最近，我们报道了淀粉在光照下也会降解。降解率通常在一天的早期较低，但随着时间的推移而上升。在这里，我们表明，光的降解率取决于相对于黎明而不是黄昏的时间。我们还表明，在光降解抑制海藻糖6-磷酸，蔗糖的可用性的信号。观察到的光降解反应可以通过骨架模型来模拟，其中降解速率是淀粉含量除以黎明前剩余时间的函数。通过扩展改进拟合，以包括海藻糖6-磷酸对淀粉降解的反馈抑制。我们还研究了可能的功能，同时淀粉的合成和降解的光，使用经验参数化模型和实验方法。这种循环缓冲了黄昏时光合作用速率下降的增长的想法得到了数据的支持，这些数据表明，在模拟黄昏的黄昏中，蛋白质和细胞壁的合成速率仍然很高。淀粉在光照下的降解也可以对抗长光周期中淀粉的过度积累，并在黄昏前后稳定信号传导。我们的结论是，在光下的淀粉降解是由类似的机制，在夜间运作，是重要的稳定碳的可用性和信号，从而优化生长在自然光条件下。淀粉在光照下的降解受与夜间相似的机制调节，稳定碳的可用性，从而优化自然光照条件下的生长
Many plants, including Arabidopsis (Arabidopsis thaliana), accumulate starch in the light and remobilize it to support maintenance and growth at night. Starch synthesis and degradation are usually viewed as temporally separate processes. Recently, we reported that starch is also degraded in the light. Degradation rates are generally low early in the day but rise with time. Here, we show that the rate of degradation in the light depends on time relative to dawn rather than dusk. We also show that degradation in the light is inhibited by trehalose 6-phosphate, a signal for sucrose availability. The observed responses of degradation in the light can be simulated by a skeletal model in which the rate of degradation is a function of starch content divided by time remaining until dawn. The fit is improved by extension to include feedback inhibition of starch degradation by trehalose 6-phosphate. We also investigate possible functions of simultaneous starch synthesis and degradation in the light, using empirically parameterized models and experimental approaches. The idea that this cycle buffers growth against falling rates of photosynthesis at twilight is supported by data showing that rates of protein and cell wall synthesis remain high during a simulated dusk twilight. Degradation of starch in the light may also counter over-accumulation of starch in long photoperiods and stabilize signaling around dusk. We conclude that starch degradation in the light is regulated by mechanisms similar to those that operate at night and is important for stabilizing carbon availability and signaling, thus optimizing growth in natural light conditions. Starch degradation in the light is regulated by similar mechanisms to those operating at night, stabilizing carbon availability, and thereby optimizing growth in natural light conditions
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影响因子：
9.9
作者：
通讯作者：
--
影响因子：
7.2
作者：
Figueroa, Carlos M.;Feil, Regina;Lunn, John E.
通讯作者：
Lunn, John E.
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：
5.6
作者：
Feugier FG;Satake A
通讯作者：
Satake A
DOI：
10.1016/0005-2728(84)90041-0
发表时间：
1984-01-01
期刊：
BIOCHIMICA ET BIOPHYSICA ACTA
影响因子：
--
作者：
DIETZ, KJ;HEBER, U
通讯作者：
HEBER, U