摘要
萜烯合成酶(TPS,terpene synthase)基因是萜类化合物生物合成途径中的关键基因,其在植物萜烯代谢中起到重要的作用。本研究以紫丁香(Syringa oblata Lindl.ex Carr.)花瓣为材料,在优化固相微萃取花香化合物条件的基础上,对4个不同花发育时期(花蕾期、初开期、盛开期和衰败期)的花香化合物进行鉴定分析;结合基因组和转录组数据筛选到了SoTPS2和SoTPS3关键候选基因,并对其进行克隆和功能研究。结果表明:(1)最适的萃取条件为30℃萃取40 min;4个花发育时期的花香总释放量呈先升高后下降的趋势,盛花期达到最高;4个时期中萜烯类化合物的释放量占花香总释放量的比例均最高,其中以单萜罗勒烯的释放量最高。(2)SoTPS2和SoTPS3基因编码区长度分别为1731 bp和1779 bp,编码氨基酸分别为576个和592个,编码的蛋白具有Terpene_cyclase_plant_C1保守结构域,属于Isoprenoid_Biosyn_C1超家族;实时荧光定量表明2个基因均在花瓣中表达量最高,在不同花发育时期表达量均呈先升高后下降趋势,在盛开期表达量最高,与单萜罗勒烯的释放量呈正相关。(3)在金鱼草(Antirrhinum majus L.)花瓣中异源瞬时过表达SoTPS2和SoTPS3基因,发现罗勒烯释放量与对照组相比分别显著增加10.91倍和23.67倍。综上表明,紫丁香花香主要成分为单萜类化合物,SoTPS2和SoTPS3可以影响紫丁香单萜化合物,尤其是罗勒烯的合成。
Terpene synthase(TPS)gene is a key regulator gene in the biosynthesis pathway of terpenoids,playing a crucial role in plant terpene metabolism.In this study,the floral fragrance components of lilac petals at different flower development stages(including bud stage,beginning stage,blooming stage and withering stage)were identified and analyzed on the basis of optimizing the floral conditions of headspace solid-phase microextraction(HS-SPME).The key candidate genes of SoTPS2 and SoTPS3 were identified by combining genome and transcriptome data,and their isolation and preliminary functional investigation were carried out.The results showed that:(1)The optimal extraction condition was 30°C for 40 min by analyzing the difference of types and release amount of volatile compounds under different extraction temperature and time.The total release of floral fragrance showed a trend of first increasing and then decreasing during the four flower development stages,and the peak(highest level)was observed at full flowering stage.Terpene compounds accounted for the highest proportion in total of floral compoents in the four periods,and the monoterpene ocimene was the highest.(2)The open reading frames(ORF)of SoTPS2 and SoTPS3 genes were 1731 bp and 1779 bp,respectively,encoding 576 and 592 amino acids.The deduced proteins have Terpene_Cyclase_Plant_C1 conservative structural domain,belonging to Isoprenoid_Biosyn_C1 superfamily.The highest transcripts of the two genes were detected in the petals via real-time PCR,and the increased expression was first detected followed by a decrease along with the flower development stages.The gene expressions positively correlated with the release of ocimene.(3)Through the transient overexpression of SoTPS2 and SoTPS3 genes in the petals of Antirrhinum majus,we observed 10.91 and 23.67-fold increased on the release of ocimene,respectively,compared with the unoverexpressed group.Collectively,the main components of floral fragrance in lilac petals are monoterpenes,and SoTPS2 and SoTPS3 as downstream regulating genes can contribute the synthesis of monoterpenes,especially ocimene.
作者
吴静
邹吉睿
汪进萱
马波
孟昕
胡增辉
冷平生
WU Jing;ZOU Jirui;WANG Jinxuan;MA Bo;MENG Xin;HU Zenghui;LENG Pingsheng(College of Landscape Architecture,Beijing University of Agriculture,Beijing 102206;Beijing Laboratory for Urban and Rural Ecological Environment,Beijing 102206;Key Laboratory of Genetics and Breeding of Trees and Flowers,Ministry of Education,Beijing 100093;National Botanical Garden,Beijing 100093)
出处
《植物遗传资源学报》
CAS
CSCD
北大核心
2024年第5期824-833,共10页
Journal of Plant Genetic Resources
基金
国家自然科学基金(31800602)
中央高校基本科研业务费专项资金资助(BFUKF202211)
北京市教委生态修复工程学高精尖学科建设项目。
关键词
紫丁香
花香
萜烯合成酶
单萜化合物
lilac
floral fragrance
terpene synthase
monoterpenes
作者简介
第一作者:吴静,研究方向为花卉分子育种,E-mail:wjmxy1988@126.com;通信作者:胡增辉,研究方向为植物生理生态,E-mail:buahuzenghui@163.com。
