John Innes Centre, Norwich NR4 7UH, United Kingdom; email:
Institute of Plant Molecular Biology, ETH Zürich, 8092 Zürich, Switzerland.
Annu Rev Plant Biol. 2020 Apr 29;71:217-245. doi: 10.1146/annurev-arplant-050718-100241. Epub 2020 Feb 19.
Research in the past decade has uncovered new and surprising information about the pathways of starch synthesis and degradation. This includes the discovery of previously unsuspected protein families required both for processes and for the long-sought mechanism of initiation of starch granules. There is also growing recognition of the central role of leaf starch turnover in making carbon available for growth across the day-night cycle. Sophisticated systems-level control mechanisms involving the circadian clock set rates of nighttime starch mobilization that maintain a steady supply of carbon until dawn and modulate partitioning of photosynthate into starch in the light, optimizing the fraction of assimilated carbon that can be used for growth. These discoveries also uncover complexities: Results from experiments with leaves in conventional controlled environments are not necessarily applicable to other organs or species or to growth in natural, fluctuating environments.
在过去的十年中，研究揭示了关于淀粉合成和降解途径的新的、令人惊讶的信息。这包括发现了以前未被怀疑的蛋白质家族，这些家族既需要这些过程，也需要长期寻求的淀粉颗粒起始机制。人们也越来越认识到叶片淀粉周转在白天-黑夜周期中为生长提供可用碳的核心作用。涉及生物钟的复杂系统级控制机制设定了夜间淀粉动员的速率，以维持稳定的碳供应，直到黎明，并调节光合作用产物在光照下向淀粉的分配，优化可用于生长的同化碳的比例。这些发现也揭示了复杂性：在传统控制环境下对叶片进行的实验结果不一定适用于其他器官或物种，也不一定适用于在自然波动环境中的生长。
