植物挥发性物质及其代谢工程

植物挥发性物质在植物之间和植物与昆虫间的化学通讯中起着重要作用.有关这些次生物质的生物合成、代谢调控、生理功能以及与环境相互作用的研究近十多年来取得了重要进展.迄今为止,已经有3 0多种植物挥发性物质的合成酶基因被克隆.这些基因调控着植物萜类、芳香化合物、脂肪酸衍生物这三大类主要挥发性物质的生物合成.由于潜在的应用价值,近几年该领域颇受注目,特别是应用基因工程技术设计植物释放特殊气味物质,诸如特定的驱避剂或者其它控制植物或昆虫行为的特殊气味乃至与人类健康相关的药用气味物质.该文就植物挥发性物质的生物合成、生理和生态功能以及基因工程方面的研究进展作一概述.

Plant Volatiles and Their Metabolic Engineering

Plant volatiles mainly includeterpenoid, benzenoid/phenylpropanoid and fatty-acid derivatives, and they play diverse roles inplant-plant and plant-insect communications. Inrecent years, great progress has been made inbiochemical and molecular characterization ofthe formation and release of these volatiles, andthis make it possible to dissect their biologicalfunctions. More than 30 kinds of genes relatedwith biosynthesis of these volatiles have beencloned. The pathways leading to synthesis ofthese metabolites can be controlled by enzymeactivity and the substrates available as well asgene architecture. Plant volatiles can serve asattractants for specific pollinators, importantcellular regulators in developmental processesand protection against environmental stress,whereas those released after herbivory or patho-gen attacks can induce the expression a set ofdefensive genes or attraction of predators of theherbivores. An attractive prospect in this area isto design scent spectrum of plant with geneticand molecular technology. Two alternative ap-proaches are used to genetically engineer theseplant volatiles. One is based on the introductionof foreign genes encoding enzymes with activi-ties that are missing in target plant, while theother is focused on modulating the expressionof native genes.