Journal of Nuclear Agricultural Sciences ›› 2021, Vol. 35 ›› Issue (8): 1751-1760.DOI: 10.11869/j.issn.100-8551.2021.08.1751

• Induced Mutations for Plant Breeding·Agricultural Biotechnology • Previous Articles     Next Articles

Cloning and Drought Response Pattern of CpNCED2, a 9-cis-epoxycarotenoid Dioxygenase Gene From Zucchini (Cucurbita pepo L.)

LIU Jianting, ZENG Meijuan, WEN Wenxu, WANG Bin, CHEN Mindong, YE Xinru, ZHU Haisheng*, WEN Qingfang*   

  1. Fujian Key Laboratory of Vegetable Genetics and Breeding/Crops Research Institute, Fujian Academy of Agricultural Sciences/Fujian Engineering Research Center for Vegetables, Fuzhou, Fujian 350013
  • Received:2020-08-04 Revised:2020-08-04 Online:2021-08-10 Published:2021-06-11

西葫芦9-顺式-环氧类胡萝卜素双加氧酶CpNCED2基因的克隆及其干旱响应模式研究

刘建汀, 曾美娟, 温文旭, 王彬, 陈敏氡, 叶新如, 朱海生*, 温庆放*   

  1. 福建省蔬菜遗传育种重点实验室/福建省农业科学院作物研究所/福建省蔬菜工程技术研究中心,福建 福州 350013
  • 通讯作者: *朱海生,男,研究员,主要从事蔬菜学研究。E-mail: zhs0246@163.com;温庆放,男,研究员,主要从事蔬菜栽培与育种研究。E-mail: fjvrc@163.com。同为通讯作者。
  • 作者简介:刘建汀,男,助理研究员,主要从事蔬菜育种生物技术研究。E-mail:ljt338625@163.com
  • 基金资助:
    国家大宗蔬菜产业技术体系福州综合实验站项目(CARS-23-G-53),福建省农业科学院科技创新平台专项(CXPT202001),福建省农业科学院青年基金项目(AGP2018-14),福建省农业科学院自由探索项目(ZYTS2019005)

Abstract: In order to explore the regulation effect of 9-cis-epoxycarotenoid dioxygenase (NCED) in response to in zucchini (Cucurbita pepo L.) the drought stress in a 1,941-bp cDNA containing a complete open reading frame (ORF) was isolated from zucchini based on a previously constructed transcriptome database, this ORF was named as CpNCED2 and predicted to encode 588 amino acids (AA) with a molecular weight (Mw) of 65.73 kDa and an isoelectric point (pⅠ) of 6.89. CpNCED2 shared about 99% identities with the homologs from Cucurbita moschata and Cucurbita maxima that both belong to the Cucurbita, indicating a relatively conservative evolution. Pfam analysis revealed that CpNCED2 has typical structural features of NCED protein family, including four conserved histidine sites (i.e., His284, His333, His398, and His575) and two NCED conserved protein domains (281~289 and 333~340 sites). The photosynthetic apparatus (i.e. GFS 3000) was used to measure the seedlings of Cucurbita pepo at 1, 2, 3, 4 d after drought treatment. Results showed that the net photosynthetic rate (Pn) of leaves decreased with the prolongation of durought treatment, and the PSII maximum photochemical efficiency (Fv/Fm), heat dissipation of photosynthesis (NPQ) and photochemical electron transport efficiency (ETR) also significantly decreased. Our results also showed that the water potential in zucchini leaves gradually decreased, whereas the abscisic acid (i.e. ABA) content gradually increased. Correspondingly, the transcript level of CpNCED2 significantly increased and reached the significant difference after 3-d treatment. Collectively, this experiment provides a theoretical basis for further research on the function of CpNCED2 gene in response to drought and ABA metablism in C. pepo.

Key words: Cucurbita pepo, drought stress, CpNCED2, abscisic acid, photosynthetic parameter, expression analysis

摘要: 为探究9-顺式-环氧类胡萝卜素双加氧酶(NCED)在西葫芦干旱胁迫环境中的调控作用,本研究基于前期构建的转录组数据库从西葫芦中分离到1条1 941 bp的cDNA,该序列包含一个完整的开放阅读框(ORF),命名为CpNCED2;基因预测编码588个氨基酸,其理论分子量(Mw)为65.73 kDa、等电点(pⅠ) 为6.89。CpNCED2与同为南瓜属的中国南瓜和印度南瓜中同源蛋白的相似性均为99%,显示出高度的保守性。Pfam分析发现,CpNCED2具有NCED家族的典型特征,即含有4个保守组氨酸位点(His284、His333、His398和His575)和2个NCED蛋白保守结构域(281~289和333~340位)。利用光合仪对干旱胁迫后1、2、3、4 d西葫芦的幼苗进行测量,结果表明,随着干旱胁迫时间的延长,叶片净光合速率(Pn)、光系统Ⅱ最大光化学效率(Fv/Fm)、非光化学淬灭系数(NPQ)和光化学电子传递效率(ETR)显著降低。同时发现,干旱胁迫后1、2、3、4 d西葫芦叶片中水势逐渐降低,脱落酸(ABA)含量逐渐升高,CpNCED2基因显著上调表达。本试验为进一步研究CpNCED2在西葫芦干旱胁迫应答以及ABA的代谢合成过程的功能提供了理论依据。

关键词: 西葫芦, 干旱胁迫, CpNCED2, 脱落酸, 光合特性, 表达分析