Wang Lu, Ruan Yong-Ling
School of Environmental and Life Sciences, University of Newcastle, Callaghan, NSW 2308, Australia.
Funct Plant Biol. 2016 Mar;43(2):105-113. doi: 10.1071/FP15249.
Roots and shoots are distantly located but functionally interdependent. The growth and development of these two organ systems compete for energy and nutrient resource, and yet, they keep a dynamic balance with each other for growth and development. The success of such a relationship depends on efficient root-shoot communication. Aside from the well-known signalling processes mediated by hormones such as auxin and cytokinin, sugars have recently been shown to act as a rapid signal to co-ordinate root and shoot development in response to endogenous and exogenous clues, in parallel to their function as carbon and energy resources for biomass production. New findings from studies on vascular fluids have provided molecular insights into the role of sugars in long-distance communications between shoot and root. In this review, we discussed phloem- and xylem- translocation of sugars and the impacts of sugar allocation and signalling on balancing root-shoot development. Also, we have taken the shoot-root carbon-nitrogen allocation as an example to illustrate the communication between the two organs through multi-layer root-shoot-root signalling circuits, comprising sugar, nitrogen, cytokinin, auxin and vascular small peptide signals.
根和地上部分相距较远，但功能上相互依存。这两个器官系统的生长和发育会竞争能量和养分资源，然而，它们在生长和发育过程中彼此保持着动态平衡。这种关系的成功取决于根 - 地上部分之间有效的信号传递。除了由生长素和细胞分裂素等激素介导的众所周知的信号传导过程外，最近研究表明，糖类除了作为生物质生产的碳和能量资源外，还作为一种快速信号，响应内源性和外源性线索来协调根和地上部分的发育。关于维管组织液的研究新发现为糖类在地上部分和根之间长距离信号传递中的作用提供了分子层面的见解。在本综述中，我们讨论了糖类在韧皮部和木质部的运输，以及糖分配和信号传导对平衡根 - 地上部分发育的影响。此外，我们以地上部分 - 根的碳 - 氮分配为例，来说明两个器官之间通过多层根 - 地上部分 - 根信号传导回路进行的信号传递，这些回路包括糖、氮、细胞分裂素、生长素和维管小分子肽信号。
