萜类化合物是松科(Pinaceae)植物中重要的代谢物,它们与松科植物生长发育、信息传递、气候适应和化学防御等关系密切,在植物生理和生态等方面具有重要功能。松科植物萜类化合物还广泛应用在制药、生物燃料以及合成化学等工业领域,具有重要的经济价值。松科植物通过甲羟戊酸途径和甲基赤藓糖磷酸途径合成所有萜类物质合成所必需的5碳前体,并在异戊烯基转移酶家族、萜类合成酶家族作用下合成单萜、倍半萜和二萜等不同长度碳链的萜类分子骨架,并进一步在细胞色素P450酶家族的作用下发生甲基化、羟基化、过氧化、糖基化等酶促反应形成具有结构极为丰富的萜类化合物。和其他次生代谢过程类似,多种酶及其基因在萜烯化合物形成过程中起到了至关重要的作用,同时,萜类化合物结构多样性的形成也主要依赖于萜类合成酶及其基因。植物中已经发现了大量的萜类合成酶,由于大量植物基因组、转录组等组学数据的公布,不断有新的萜类合成酶被报道。笔者介绍了植物萜类化合物前体的合成途径及其关键酶基因、植物萜类合成酶的结构和类型,着重阐述松科植物萜类合成酶结构、功能以及相应基因家族鉴定和系统分类的研究进展,并针对松科植物萜类合成酶及其基因研究领域存在的研究树种偏少、松科植物萜烯类代谢可能存在的特异代谢路径重视程度不够、适用于针叶树种相关基因的功能研究平台搭建欠缺、多基因网络调控松科植物萜烯类合成机制研究未得到系统开展、产脂和抗逆相关的松科植物关键基因未得到挖掘与利用等相关问题提出了建议,以期为松科植物萜类生物合成机制解析及松科植物遗传改良提供参考。

Terpenoids are important metabolites that are involved in several processes such as growth and development, information transmission, climatic acclimation and chemical defense in Pinaceae plants and have important physiological and ecological functions. Terpenoids from Pinaceae plants have an important economic value because they are widely applied in the pharmaceutical, biofuel, chemical synthesis and other industries. The mevalonate and methylerythrose phosphate pathways lead to the synthesis of the five-carbon precursors of all plant terpenoids. Terpene molecular skeletons with different carbon chain lengths, such as monoterpenes, sesquiterpenes and diterpenes are synthesized by the isoprene and terpene synthase families. Furthermore, cytochrome P450 enzymatic reactions such as methylation, hydroxylation, peroxidation and glycosylation result in the formation of a large family of terpenoids with extremely rich structures. The enzymes and genes involved in the biochemical synthesis of terpenes play important roles during these processes and also influence the structural diversity of terpenoids. Terpene synthases are abundant in plants, and new terpene synthases have recently been discovered due to the accumulation of plant genomic and transcriptomic data. This article describes the synthesis of plant terpenoid precursors and their key enzyme genes, the structures, types and functions of terpene synthases, as well as the identification and phylogeny of the terpene synthase gene family in Pinaceae. The article also offers suggestions regarding related practical issues, such as the need for research into terpine synthase and genes in Pinus species. The specific pathways involved in the terpene metabolism in Pinaceae remain unknown, a functional research platform for the related genes of coniferous species has not been established, and the mechanism of the multi-gene network regulating the synthesis of terpenes in Pinaceae has not been systematically investigated. Furthermore, the key genes of Pinaceae associated with lipid production and stress resistance have not been exploited. These issues should be addressed to provide a reference for understanding the molecular mechanisms of terpenoid biosynthesis and genetically improving Pineae.