高、低硝态氮营养条件下烟草根系基因表达谱及代谢途径的差异分析  

Analysis of gene expression profile and metabolic pathway of tobacco root at high and low levels of nitrate nitrogen

作　　者：张玉宁 史宏志[1] 王景[1] 周炎[1] 杨惠娟[1] ZHANG Yuning;SHI Hongzhi;WANG Jing;ZHOU Yan;YANG Huijuan(National Tobacco Cultivation & Physiology & Biochemistry Research Center, College of Tobacco Science, Henan Agricultural University, Zhengzhou 450002, China)

机构地区：[1]河南农业大学烟草学院国家烟草栽培生理生化基地,郑州市金水区农业路63号450002

出　　处：《烟草科技》2019年第4期1-8,共8页Tobacco Science & Technology

基　　金：中国烟草总公司烟草行业烟草栽培重点实验室项目"烟草硝酸还原及其调控"(YCZP201502)

摘　　要：为探索烟草根系对硝酸根信号的响应机制,以烤烟品种K326为材料在温室中(14 h光照,10 h黑暗,温度28℃,相对湿度65%～75%)进行烟苗培养及氮胁迫处理,并利用转录组测序方法研究了烤烟根系在高浓度(硝酸根浓度为5.0 mmol/L)与低浓度(硝酸根浓度为0.1 mmol/L)硝态氮营养条件下分别处理0、6、12和24 h的基因表达差异。KEGG(Kyoto Encyclopedia of Genes and Genomes)代谢途径分析表明,高氮和低氮营养条件下处理6 h时Sub-cluster亚群中一些差异表达基因表达量先上调而后又下降,这些基因主要集中在苯丙素生物合成,丙氨酸、天冬氨酸和谷氨酸代谢等途径中。说明氨基酸、碳氮代谢途径是响应不同氮营养条件的重要代谢途径。而一些参与托品烷、哌啶和吡啶生物碱的生物合成,嘧啶和嘌呤代谢,果糖和甘露糖代谢,淀粉和蔗糖代谢等多条途径涉及的基因在低浓度氮营养胁迫下呈下降趋势,而在高浓度氮营养胁迫下差异表达基因表达量呈上升趋势,表明低浓度氮营养抑制了烤烟根部生物碱的合成以及能量代谢相关途径的代谢活动,而高浓度氮营养则表现为促进作用。To investigate the responses of tobacco roots to nitrate signals, taking flue-cured tobacco variety K326 as experimental material, seedling culture and nitrogen stress experiments were conducted in a greenhouse with controlled light, temperature and humidty (14 h light, 10 h dark, temperature 28 ℃, relative humidity 65%-75%) and transcriptome sequencing technique was used to study the differentially expressed genes (DEGs) in tobacco roots at high (NO3- 5.0 mmol/L) and low (NO3- 0.1 mmol/L) levels of nitrate nitrogen applying after 0, 6, 12 and 24 h. KEGG (Kyoto Encyclopedia of Genes and Genomes) pathway analysis showed that the expressions of some DEGs in sub-cluster increased first and then decreased at high and low levels of nitrate nitrogen applying after 6 h. These genes were mapped in phenylpropanoid biosynthesis and the metabolic pathways of alanine, aspartic acid and glutamic acid. The results indicated that the metabolism pathways of amino acids and carbon/nitrogen were important to respond nitrogen signal. However, some genes were involved in the biosynthesis of tropone, piperidine and pyridine alkaloid. The metabolism pathways of pyrimidine, purine, fructose, mannose, starch and sucrose down-regulated at the low level of nitrate nitrogen while they up-regulated at the high level of nitrate nitrogen, which suggested that the alkaloid synthesis and energy metabolism in flue-cured tobacco roots were inhibited at the low level of nitrate nitrogen and were promoted at the high level of nitrate nitrogen.

关 键 词：烟草 氮营养 硝酸根信号 转录组分析 

分 类 号：TS413[农业科学—烟草工业]