生物技术通报 ›› 2026, Vol. 42 ›› Issue (11): 222-229.doi: 10.13560/j.cnki.biotech.bull.1985.2026-0173

• 研究报告 • 上一篇    

日本落叶松LkNiR启动子的克隆及表达特性分析

武郁洁, 王宇倩, 刘翠双, 郁羽宵, 耿静泽, 盖颖()   

  1. 1.林木遗传育种全国重点实验室 北京林业大学生物科学与技术学院,北京 100083
    2.树木花卉育种生物工程国家林业和草原局重点 实验室,北京 100083
  • 收稿日期:2026-02-04 出版日期:2026-11-26 发布日期:2026-11-03
  • 通讯作者: 盖颖gaiying@bjfu.edu.cn
  • 基金资助:
    国家重点研发计划项目(2022YFD2200100)

Cloning and Expression Characteristics Analysis of LkNiR Promoter from Larix kaempferi

WU Yu-jie, WANG Yu-qian, LIU Cui-shuang, YU Yu-xiao, GENG Jing-ze, GAI Ying()   

  1. 1.State Key Laboratory of Tree Genetics and Breeding, College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083
    2.The Tree and Ornamental Plant Breeding and Biotechnology Laboratory of National Forestry and Grassland Administration, Beijing 100083
  • Received:2026-02-04 Published:2026-11-26 Online:2026-11-03

摘要:

目的 亚硝酸盐还原酶(nitrite reductase, NiR)是植物氮同化关键酶,可催化亚硝酸盐还原为铵态氮,保障氮同化高效进行。研究日本落叶松(Larix kaempferi)LkNiR基因启动子的表达特性及亚硝酸盐胁迫响应规律,为选育氮高效利用型林木品种提供理论支撑。 方法 从日本落叶松基因组DNA中克隆LkNiR启动子序列,利用PlantCARE与PLACE数据库预测顺式作用元件;构建LkNiR-GFP报告载体,通过农杆菌介导的遗传转化获得转基因烟草(Nicotiana tabacum)及日本落叶松毛状根,结合PCR鉴定、荧光观察与RT-qPCR技术检测启动子活性;以100 mmol/L亚硝酸钠处理日本落叶松幼苗,采用RT-qPCR技术分析LkNiR基因的时序表达模式。 结果 LkNiR基因启动子(登录号:PV700087)全长1 941 bp,含TATA-box、CAAT-box等核心元件及多种激素与胁迫响应元件,LkNiR启动子含9个氮同化响应顺式元件。该启动子在转基因烟草中呈现组织偏好性表达,在根中活性较CaMV35S启动子高92.1%,在落叶松毛状根中活性较CaMV35S启动子高103.3%。亚硝酸盐胁迫下,LkNiR基因表达呈时空分化,根中早期快速响应,茎中响应平缓,叶中诱导最强且持续。 结论 LkNiR启动子具有明显的根部偏好表达特性,其活性受亚硝酸盐信号诱导且具有时空分化特征,在日本落叶松氮同化与逆境响应过程中发挥关键调控作用。

关键词: 亚硝酸盐还原酶, 启动子, 日本落叶松, 毛状根, 氮同化, 亚硝酸盐胁迫, 顺式作用元件, 表达分析

Abstract:

Objective Nitrite reductase (NiR) is a key plant nitrogen assimilation enzyme that catalyzes nitrite reduction to ammonium nitrogen and ensures efficient nitrogen assimilation. This study investigated Larix kaempferiLkNiR promoter expression features and nitrite stress response mechanisms and provided theoretical support for breeding forest trees with high nitrogen use efficiency. Method The LkNiR promoter sequence was cloned from L. kaempferi genomic DNA, and screened for cis-acting elements using PlantCARE and PLACE databases. The LkNiR-GFP reporter vector was constructed, and transgenic tobacco as well as L. kaempferi hairy roots were obtained via Agrobacterium-mediated genetic transformation. Promoter activity was detected by PCR identification, fluorescence observation, and RT-qPCR assays. L. kaempferi seedlings were treated with 100 mmol/L sodium nitrite, and the LkNiR gene temporal expression pattern was analyzed via RT-qPCR. Result The full-length LkNiR gene promoter (Accession No.: PV700087) was 1 941 bp, containing core elements (e.g., TATA-box, CAAT-box), multiple hormone-responsive elements, and stress-responsive elements. Notably, the LkNiR promoter harbored nine cis-acting elements involved in nitrogen assimilation. The promoter exhibited tissue-preferential expression in transgenic tobacco, with 92.1% higher activity in roots than the CaMV35S promoter, and 103.3% higher activity in L. kaempferi hairy roots than the CaMV35S promoter. Under nitrite stress, LkNiR expression showed spatiotemporal divergence: roots displayed a rapid early response, stems exhibited a moderate response, and needles had the strongest and most sustained induction. Conclusion The LkNiR promoter exhibits significant root-preferential expression characteristics, its activity is induced by nitrite signaling and shows spatiotemporal differentiation features, and it plays a key regulatory role in nitrogen assimilation and stress response in L. kaempferi.

Key words: nitrite reductase, promoter, Larix kaempferi, hairy root, nitrogen assimilation, nitrite stress, cis-acting elements, expression analysis