Williams L E, Lemoine R, Sauer N
School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton, UK SO16 7PX.
Trends Plant Sci. 2000 Jul;5(7):283-90. doi: 10.1016/s1360-1385(00)01681-2.
Sugar-transport proteins play a crucial role in the cell-to-cell and long-distance distribution of sugars throughout the plant. In the past decade, genes encoding sugar transporters (or carriers) have been identified, functionally expressed in heterologous systems, and studied with respect to their spatial and temporal expression. Higher plants possess two distinct families of sugar carriers: the disaccharide transporters that primarily catalyse sucrose transport and the monosaccharide transporters that mediate the transport of a variable range of monosaccharides. The tissue and cellular expression pattern of the respective genes indicates their specific and sometimes unique physiological tasks. Some play a purely nutritional role and supply sugars to cells for growth and development, whereas others are involved in generating osmotic gradients required to drive mass flow or movement. Intriguingly, some carriers might be involved in signalling. Various levels of control regulate these sugar transporters during plant development and when the normal environment is perturbed. This article focuses on members of the monosaccharide transporter and disaccharide transporter families, providing details about their structure, function and regulation. The tissue and cellular distribution of these sugar transporters suggests that they have interesting physiological roles.
糖转运蛋白在植物体内糖的细胞间和长距离运输中起着至关重要的作用。在过去十年中，编码糖转运体（或载体）的基因已被鉴定出来，在异源系统中进行了功能表达，并对其时空表达进行了研究。高等植物拥有两类不同的糖载体家族：主要催化蔗糖运输的二糖转运体和介导多种单糖运输的单糖转运体。各基因的组织和细胞表达模式表明了它们特定的、有时是独特的生理功能。一些糖载体仅起营养作用，为细胞生长和发育提供糖类，而另一些则参与产生驱动物质流动或移动所需的渗透梯度。有趣的是，一些载体可能参与信号传导。在植物发育过程以及正常环境受到干扰时，多种调控水平对这些糖转运体进行调节。本文重点介绍单糖转运体和二糖转运体家族的成员，详细阐述它们的结构、功能和调控。这些糖转运体的组织和细胞分布表明它们具有有趣的生理功能。
