浙江农业学报 ›› 2026, Vol. 38 ›› Issue (8): 1598-1609.DOI: 10.3969/j.issn.1004-1524.20250609

• 园艺科学 • 上一篇    下一篇

斑地锦EmPAL基因克隆、表达模式和酶活性分析

吴晴阳1(), 桂明明2, 宋美玲1, 郭三保3, 张志高4, 黄胜和2,*()   

  1. 1 抚州医药学院 医学基础部, 江西 抚州 344000
    2 抚州医药学院 江西省教育厅建昌帮中药研究重点实验室, 江西 抚州 344000
    3 抚州医药学院 药学系, 江西 抚州 344000
    4 江西省烟草公司抚州市公司, 江西 抚州 344000
  • 收稿日期:2025-09-18 出版日期:2026-08-25 发布日期:2026-09-14
  • 作者简介:吴晴阳,从事植物基因和生理学研究。E-mail:825166405@qq.com
  • 通讯作者: *黄胜和,E-mail:hsh712@163.com
  • 基金资助:
    江西省教育厅科学技术研究项目(GJJ2205908);江西中医药高等专科学校科研项目(2024XJKY01)

Cloning, expression pattern, and enzyme activity analysis of the phenylalanine ammonia-lyase gene (EmPAL) in Euphorbia maculata

WU Qingyang1(), GUI Mingming2, SONG Meiling1, GUO Sanbao3, ZHANG Zhigao4, HUANG Shenghe2,*()   

  1. 1 Department of Basic Medicine, Fuzhou Medical College, Fuzhou 344000, Jiangxi, China
    2 Key Laboratory of Jianchangbang Traditional Chinese Medicine Research of Jiangxi Education Institutes, Fuzhou Medical College, Fuzhou 344000,Jiangxi, China
    3 Department of Pharmacy, Fuzhou Medical College, Fuzhou 344000,Jiangxi, China
    4 Fuzhou Branch of Jiangxi Tobacco Company, Fuzhou 344000,Jiangxi, China
  • Received:2025-09-18 Published:2026-08-25 Online:2026-09-14

摘要:

为解析药用植物斑地锦(Euphorbia maculata)药效成分黄酮类化合物生物合成途径结构基因苯丙氨酸解氨酶(phenylalanine ammonia-lyase,EmPAL)基因结构和蛋白质功能,为后续深入研究EmPAL提供参考,以斑地锦为材料,基于转录组数据结合cDNA 3'末端快速扩增(3'-RACE)和交错式热不对称PCR(Tail-PCR),克隆了EmPAL的开放阅读框(open reading frame, ORF)和启动子序列。采用生物信息学工具分析了EmPAL的理化性质、结构及系统发育关系。通过实时荧光定量PCR(RT-qPCR)检测EmPAL在不同组织中的表达模式。此外,还进行了原核表达并通过体外酶活性试验验证了其催化功能。结果表明,EmPAL基因ORF长度2 160 bp,编码719个氨基酸,其启动子含有光反应、胁迫应答元件和苯丙烷类元件等顺式作用元件。组织表达分析显示,EmPAL基因在斑地锦生殖生长期的根中表达量最高。EmPAL蛋白分子量为78.17 ku,等电点(pI)6.34,二级结构以α螺旋为主,三级结构为典型的“海马”状,四级结构为四聚体。原核表达与体外酶活性试验证实,EmPAL可催化苯丙氨酸生成反式肉桂酸,最适温度为60 ℃。本研究为深入解析EmPAL基因功能及其调控斑地锦中黄酮类化合物的生物合成提供了理论依据。

关键词: 斑地锦, EmPAL, 启动子, 克隆, 实时荧光定量PCR, 原核表达, 酶活性

Abstract:

This study aimed to elucidate the structure and protein function of the phenylalanine ammonia-lyase gene (EmPAL), a structural gene in the flavonoid biosynthesis pathway in the medicinal plant Euphorbia maculata, and to provide a basis for further functional investigation of EmPAL. Using E. maculata as the material, the open reading frame (ORF) and promoter sequence of EmPAL were cloned based on transcriptome data combined with 3'-RACE and Tail-PCR techniques. Bioinformatics tools were employed to analyze the physicochemical properties, structural characteristics, and phylogenetic relationships of EmPAL. The expression pattern of EmPAL in different tissues of E. maculata was examined using quantitative real-time PCR (RT-qPCR). Furthermore, prokaryotic expression was performed and its catalytic function was validated through in vitro enzyme activity assays. The results showed that the ORF of EmPAL was 2 160 bp in length, encoding 719 amino acids. The promoter region contained cis-acting elements related to light response, stress response, and phenylpropanoid metabolism regulation. Tissue-specific expression analysis revealed that EmPAL expression was highest in the roots during the reproductive growth period. The molecular weight of EmPAL protein is 78.17 ku, and its isoelectric point is 6.34. The secondary structure was predominantly composed of alpha helix, the tertiary structure exhibited a typical “sea horse” shape, and the quaternary structure was a tetramer. Prokaryotic expression and in vitro enzyme activity assays confirmed that EmPAL could catalyze the conversion of phenylalanine to trans-cinnamic acid, with an optimal reaction temperature of 60 ℃. This study provides a theoretical foundation for further investigation into the function of EmPAL and its role in regulating the biosynthesis of flavonoids in E. maculata.

Key words: Euphorbia maculata, EmPAL, promoter, cloning, RT-qPCR, prokaryotic expression, enzyme activity

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