DNA甲基化参与调控马铃薯响应干旱胁迫的关键基因挖掘  

Key genes mining of DNA methylation involved in regulating drought stress response in potato

作　　者：李鹏程 毕真真 孙超 秦天元[1,2] 梁文君 王一好 许德蓉 刘玉汇 张俊莲[1,2] 白江平[1,2] LI Peng-Cheng;BI Zhen-Zhen;SUN Chao;QIN Tian-Yuan;LIANG Wen-Jun;WANG Yi-Hao;XU De-Rong;LIU Yu-Hui;ZHANG Jun-Lian;BAI Jiang-Ping(Gansu Provincial Key Laboratory of Aridland Crop Science/Gansu Key Laboratory of Crop Improvement&Germplasm Enhancement,Lanzhou 730070,Gansu,China;College of Agronomy,Gansu Agricultural University,Lanzhou 730070,Gansu,China)

机构地区：[1]甘肃省干旱生境作物学重点实验室/甘肃省作物遗传改良与种质创新重点实验室,甘肃兰州730070 [2]甘肃农业大学农学院,甘肃兰州730070

出　　处：《作物学报》2021年第4期599-612,共14页Acta Agronomica Sinica

基　　金：国家自然科学基金项目(31660432,31960442);国家现代农业产业技术体系建设专项(CARS-09-P14);甘肃省马铃薯产业体系(GARS-03-P1);甘肃农业大学引进人才专项科研项目(2017RCZX-01);甘肃省科技厅项目(18JR3RA170)资助。

摘　　要：植物受到干旱胁迫时,会通过DNA甲基化做出快速反应以帮助其应对胁迫。为探究在干旱胁迫下,DNA甲基化是如何影响基因转录表达,本研究对甘露醇模拟干旱和5-azadC(去甲基化)处理下,抗旱性不同的2个马铃薯品种(抗旱型,青薯9号;干旱敏感型,大西洋)进行转录组学分析,以Fold-change>2和校正后P<0.01进行差异表达基因(DEG)的筛选。GO富集分析发现,2种处理都共同显著富集到氧化应激和碳水化合物代谢过程相关的GO term。说明不同耐旱性马铃薯在响应干旱胁迫时,与这些GO term相关的基因也受DNA去甲基化调控。对既响应干旱又响应DNA去甲基化的1345个DEG进行KEGG功能富集发现,与植物抗旱相关的通路有植物MAPK信号途径、植物激素信号转导途径、植物谷胱甘肽代谢通路、糖酵解与糖异生和磷酸肌醇代谢通路。说明这些通路相关基因在大西洋和青薯9号2个抗旱性不同的马铃薯品种中,响应干旱的敏感性受DNA甲基化调控。接着对DEG上游1500 bp启动子区域进行顺式作用原件和甲基化CpG岛分析发现,干旱胁迫下参与植物谷胱甘肽代谢的GST基因通过DNA去甲基化来降低启动子区ABRE和CAAT-box作用元件的甲基化水平,进而激活该基因的表达以应对干旱胁迫。因此,利用比较转录组学分析干旱和DNA去甲基化处理下的差异基因,可挖掘到DNA甲基化参与调控马铃薯响应干旱胁迫的相关基因,为研究马铃薯干旱胁迫响应的表观遗传学机理提供新的研究思路。When plants are subjected to water stress,they will make a rapid response to drought stress through DNA methylation.In order to study how DNA methylation affects the transcriptional expression of genes under drought stress in potato,comparative transcriptomic analysis was carried out on two potato varieties with different drought resistances,which were planted under mannitol simulated drought and 5-azadC treatments.The differentially expressed genes(DEGs)were identified by Fold-change>2 and corrected P<0.01.Then DEGs were subjected to GO enrichment analysis.The results showed that these DEGs were enriched in the oxidative stress and carbohydrate metabolism,suggesting these GO term-related genes were also regulated by DNA demethylation,responded to drought stress in different drought-tolerant potatoes.The common 1345 DEGs both responding to drought stress and DNA demethylation were functionally enriched by KEGG pathway.The results showed that plant MAPK signal pathway,plant hormone signal transduction pathway,plant glutathione metabolism pathway,glycolysis and glutathione metabolism pathway and inositol phosphate metabolism pathway were related to plant drought resistance.It was suggested that the sensitivity of these pathway-related genes responding to drought stress were regulated by DNA methylation in Atlantic and Qingshu 9.The cis-acting elements and methylated CpG islands were analyzed in the 1500 bp promoter region of DEGs.The results showed that the methylation level of ABRE and CAAT-box acting elements in the promoter region of GST gene involved in plant glutathione metabolism were reduced through DNA demethylation under drought stress.Then the expression was activated in response to drought stress.Therefore,DEGs under drought and DNA demethylation treatments could be analyzed using comparative transcriptomic,and then the genes related to DNA methylation involved in regulating drought stress response in potato could be found.These results provide a new idea for further studying the epigenetic mechanism of

关 键 词：马铃薯 干旱胁迫 DNA甲基化 转录组 谷胱甘肽S转移酶 

分 类 号：S532[农业科学—作物学]