AtDREB1A基因过量表达对马铃薯生长及抗非生物胁迫基因表达的影响
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摘要
为明确AtDREB1A基因过量表达对马铃薯生长及基因表达的影响,以马铃薯品种陇薯3号(L3)及其AtDREB1A转基因株系T2为材料,采用盆栽试验,在马铃薯盛花期将盆土含水量控制为田间最大持水量(FWC)的45%～50%,观察转基因前后植株表型,并研究叶片MDA含量、RWC、SOD和POD活性及其基因表达的差异。结果表明,正常浇水条件下2个株系各指标差异不大。胁迫20 d后,转基因植株T2的表型明显好于对照L3,且RWC显著高于L3;各株系叶片的MDA含量、SOD和POD活性均明显上升,但转基因植株MDA含量上升幅度较对照小,抗氧化保护酶SOD、POD活性升高幅度较对照大,说明转基因植株细胞膜损伤和膜脂过氧化程度较轻,植株的耐旱性明显提高。转录组测序及生物信息学分析发现,转基因材料T2相对于L3的差异表达基因共430个,其中上调表达基因287个,下调表达基因143个。功能注释和显著性富集结果表明,差异表达基因富集涉及GO功能分类体系中生物过程、细胞组分和分子功能3个大类别,且大部分集中在细胞内和膜上,主要涉及信号传导、氧化还原、生物调解、应激反应、发育过程、系统免疫过程、核酸和蛋白结合转录因子活性、转运活性及催化活性。其中抗非生物胁迫相关蛋白PPR、HSP、P450、MLO等家族的大量基因表达量发生较大变化,说明这些基因在转AtDREB1A基因马铃薯抵御干旱过程中发挥着非常重要的作用。本研究为进一步解析AtDREB1A基因提高马铃薯抗旱性的调控网络奠定了基础。
Longshu 3(L3) and its AtDREB1A transgenic line T2 were planted in the pot experiment. The water content of the soil in pots was controlled to 45%–50% of the maximum water holding capacity(FWC) during the flowering stage of the potato. The phenotype, MDA content, RWC, activities of SOD and POD, and the gene expression level in leaves were analyzed, showing there were no significant differences between the two lines under normal watering conditions. After 20 d of stress treatment, the phenotype of transgenic plants T2 was significantly better than that of control L3, and RWC was significantly higher than that of L3. The MDA content, SOD and POD activities of leaves in each line increased significantly, while the MDA content of transgenic plants increased less than, and the activities of SOD and POD of transgenic plants increased more than those of the control,indicating that the cell membrane damage and membrane lipid peroxidation of the transgenic plants were lighter than those of the control, and the drought tolerance of transgenic plants was significantly improved. Transcriptome sequencing and bioinformatic analysis showed that compared with L3, there were 430 differentially expressed genes in T2, including 287 up-regulated genes and 143 down-regulated genes. Functional annotation and significance enrichment showed that all differentially expressed genes were involved in three broad categories of GO functional classification systems, that was biological processes, cell components and molecular functions. Most of these differentially expressed genes concentrated on the membrane in cells, and mainly related to signal transduction, redox, biological mediation, stress response, development process, system immune process, nucleic acid and protein binding transcription factor activity, transport activity and catalytic activity. The expression of a large number of abiotic stress-related genes was up-regulated, including PPR protein family, P450 protein family, heat shock protein family and MLO protein family, indicating that these genes play a very important role in drought-stress resistance of AtDREB1A transgenic potato. This study lays a foundation for further understanding AtDREB1A's regulatory network to improve potato drought resistance.
Longshu 3(L3) and its AtDREB1A transgenic line T2 were planted in the pot experiment. The water content of the soil in pots was controlled to 45%–50% of the maximum water holding capacity(FWC) during the flowering stage of the potato. The phenotype, MDA content, RWC, activities of SOD and POD, and the gene expression level in leaves were analyzed, showing there were no significant differences between the two lines under normal watering conditions. After 20 d of stress treatment, the phenotype of transgenic plants T2 was significantly better than that of control L3, and RWC was significantly higher than that of L3. The MDA content, SOD and POD activities of leaves in each line increased significantly, while the MDA content of transgenic plants increased less than, and the activities of SOD and POD of transgenic plants increased more than those of the control,indicating that the cell membrane damage and membrane lipid peroxidation of the transgenic plants were lighter than those of the control, and the drought tolerance of transgenic plants was significantly improved. Transcriptome sequencing and bioinformatic analysis showed that compared with L3, there were 430 differentially expressed genes in T2, including 287 up-regulated genes and 143 down-regulated genes. Functional annotation and significance enrichment showed that all differentially expressed genes were involved in three broad categories of GO functional classification systems, that was biological processes, cell components and molecular functions. Most of these differentially expressed genes concentrated on the membrane in cells, and mainly related to signal transduction, redox, biological mediation, stress response, development process, system immune process, nucleic acid and protein binding transcription factor activity, transport activity and catalytic activity. The expression of a large number of abiotic stress-related genes was up-regulated, including PPR protein family, P450 protein family, heat shock protein family and MLO protein family, indicating that these genes play a very important role in drought-stress resistance of AtDREB1A transgenic potato. This study lays a foundation for further understanding AtDREB1A's regulatory network to improve potato drought resistance.
引文
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[19]范敏,金黎平,刘庆昌,屈冬玉.马铃薯PPR蛋白家族基因SoDIPPR的克隆及其在干旱条件下的表达特征分析.中国农业科学,2008,41:2249-2257.Fan M,Jin L P,Liu Q C,Qu D Y.Cloning of SoDIPPR gene of pentatricopeptide repeat(PPR)protein family in potato and analysis of expression characteristics under drought conditions.Sci Agric Sin,2008,41:2249-2257(in Chinese with English abstract).
[20]Yan S P,Zhang Q Y,Tang Z C,Su W A,Sun W N.Comparative proteomic analysis provides new insights into chilling stress responses in rice.Mol Cell Proteomics,2006,5:484-496.
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[2]Fowler S,Thomashow M F.Arabidopsis transcription profiling indicates that multiple regulatory pathways are activated during cold acclimation in addition to the CBF cold response pathway.Plant Cell,2002,14:1675-1690.
[3]王萍,高世庆,郭永来,程宪国,王罡,马有志,季静.利用农杆菌介导将抗逆相关基因GmDREB导入大豆的研究.大豆科学,2008,27:47-51.Wang P,Gao S Q,Guo Y L,Cheng X G,Wang Z,Ma Y Z,Ji J.Transformation of stress resistance related gene GmDREB into soybean via Agrobacterium-mediation.Soybean Sci,2008,27:47-51(in Chinese with English abstract).
[4]Courtois B,McLaren G,Sinha P K,Prasad K,Yadav R,Shen L.Mapping QTLs associated with drought avoidance in upland rice.Mol Breed,2000,6:55-66.
[5]刘录祥,赵林姝,梁欣欣,郑企成,刘强,王晶,郭会君,赵世荣,陈文华.基因枪法获得逆境诱导转录因子DREB1A转基因小麦的研究.中国生物工程杂志,2003,23(11):53-56.Liu L X,Zhao L S,Liang X X,Zheng Q C,Liu Q,Wang J,Guo H J,Zhao S R,Chen W H.Study on production of transgenic wheat with a stress-inducible transcription factor gene DREB1Aby microprojectile bombardment.China Biotechnol,2003,23(11):53-56(in Chinese with English abstract).
[6]Pellegrineschi A,Reynolds M,Pacheco M,Brito R M,Almeraya R,Yamaguchi-Shinozaki K,Hoisington D.Stress-induced expression in wheat of the Arobidopsls thaliana DREB1A gene delays water stress symptoms under greenhouse conditions.Geneme,2004,47:493-500.
[7]许昆朋.转At CBF3基因马铃薯提高抗冷性的研究.山东农业大学硕士毕业论文,山东泰安,2011.Xu K P.Studies on the Mechanisms of Enhanced Chilling Tolerance in Potato Transformed with AtCBF3 Gene.MS Thesis of Shandong Agricultural University,Tai’an,Shandong,China,2011(in Chinese with English abstract).
[8]Dou H O,Xu K P,Meng Q W,Li G,Yang X H.Potato plants ectopically expressing Arabidopsis thaliana CBF3 exhibit enhanced tolerance to high-temperature stress.Plant Cell Environ,2014,38:61-72.
[9]贾小霞,齐恩芳,王一航,文国宏,龚成文,王红梅,李建武,马胜,胡新元.转录因子DREB1A基因和Bar基因双价植物表达载体的构建及对马铃薯遗传转化的研究.草业学报,2014,23(3):110-114.Jia X X,Qi E F,Wang Y H,Wen G H,Gong C W,Wang H M,Li J W,Ma S,Hu X Y.Construction of a bivalent plant expression vector of DREB1A and Bar genes and studies of genetic transformation of potato.Acta Pratac Sin,2014,23(3):110-114(in Chinese with English abstract).
[10]贾小霞,齐恩芳,马胜,胡新元,王一航,文国宏,龚成文,李建武.转DREB1A/Bar双价基因马铃薯的耐旱性及除草剂抗性分析.草业学报,2015,24(11):58-64.Jia X X,Qi E F,Ma S,Hu X Y,Wang Y H,Wen G H,Gong C W,Li J W.Analysis of drought tolerance and herbicide resistance in transgenic potato plants over-expressing DREB1A/Bar.Acta Pratacul Sin,2015,24(11):58-64(in Chinese with English abstract).
[11]张治安,张美善,蔚荣海.植物生理学实验指导.北京:中国农业科学技术出版社,2004.pp 265-296.Zhang Z A,Zhang M S,Wei R H.Plant Physiology Experiment Guide.Beijing:China Agricultural Science and Technology Press,2004.pp 265-296(in Chinese).
[12]康雯.土壤自然失水胁迫对地锦幼苗生理生化特性的影响.东北林业大学硕士学位论文,黑龙江哈尔滨,2010.Kang W.Effect of Soil Natural Water Stress on Physiological and Biochemical Indexes in Parthenocissus tricuspidata Seedling.MS Thesis of Northeast Forestry University,Harbin,Heilongjiang,China,2010(in Chinese with English abstract).
[13]许冰霞,尹美强,温银元,裴帅帅,柯贞进,张彬,原向阳.谷子萌发期响应干旱胁迫的基因表达谱分析.中国农业科学,2018,51:1431-1447.Xu B X,Yin M Q,Wen Y Y,Pei S S,Ke Z J,Zhang B,Yuan X Y.Gene expression profiling of foxtail millet(Setaria italica L.)under drought stress during germination.Sci Agric Sin,2018,51:1431-1447(in Chinese with English abstract).
[14]李健.ScCBF1与StCBF1转录因子在马铃薯应答低温、干旱及盐胁迫过程中存在功能差异.山东农业大学硕士学位论文,山东泰安,2018.Li J.ScCBF1 and StCBF1 have Different Function in Response to Freezing,Drought and Salt Stress in Potato.MS Thesis of Shandong Agricultural University,Tai’an,Shandong,China,2018(in Chinese with English abstract).
[15]杜建雄,侯向阳,刘金荣.草地早熟禾对干旱及旱后复水的生理响应研究.草业学报,2010,19(2):31-38.Du J X,Hou X Y,Liu J R.A study on physiological response to drought and re-watering treatments in Kentucky bluegrass.Acta Pratac Sin,2010,19(2):31-38(in Chinese with English abstract).
[16]刘明稀,卢少云,郭振飞.假俭草抗旱变异体的筛选及其生理鉴定.草业学报,2012,21(1):126-132.Liu M X,Lu S Y,Guo Z F.Selection and physiological identification of somaclonal variants for increased drought resistance of centipedegrass.Acta Pratac Sin,2012,21(1):126-132(in Chinese with English abstract).
[17]李源,刘贵波,高洪文,孙桂枝,赵海明,谢楠.紫花苜蓿种质耐盐性综合评价及盐胁迫下的生理反应.草业学报,2010,19(4):79-86.Li Y,Liu G B,Gao H W,Sui G Z,Zhao H M,Xie N.A comprehensive evaluation of salt-tolerance and the physiological response of Medicago sativa at the seedling stage.Acta Pratac Sin,2010,19(4):79-86(in Chinese with English abstract).
[18]张海娜,李小娟,李存东,肖恺.过量表达小麦超氧化物歧化酶(SOD)基因对烟草耐盐能力的影响.作物学报,2008,34:1403-1408.Zhang H N,Li X J,Li C D,Xiao K.Effects of overexpression of wheat superoxide dismutase(SOD)genes on salt tolerant capability in tobacco.Acta Agron Sin,2008,34:1403-1408(in Chinese with English abstract).
[19]范敏,金黎平,刘庆昌,屈冬玉.马铃薯PPR蛋白家族基因SoDIPPR的克隆及其在干旱条件下的表达特征分析.中国农业科学,2008,41:2249-2257.Fan M,Jin L P,Liu Q C,Qu D Y.Cloning of SoDIPPR gene of pentatricopeptide repeat(PPR)protein family in potato and analysis of expression characteristics under drought conditions.Sci Agric Sin,2008,41:2249-2257(in Chinese with English abstract).
[20]Yan S P,Zhang Q Y,Tang Z C,Su W A,Sun W N.Comparative proteomic analysis provides new insights into chilling stress responses in rice.Mol Cell Proteomics,2006,5:484-496.
[21]Baldwin J C,Dombrowski J E.Evaluation of Lolium temulentum as a model grass species for the study of salinity stress by PCR-based subtractive suppression hybridization analysis.Plant Sci,2006,171:459-469.
[22]Ma S,Gong Q,Bohnert H J.Dissecting salt stress pathways.JExp Bot,2006,57:1097-1107.
[23]Baxter C J,Redestig H,Schauer N,Repsilber D,Patil K R,Nielsen J,Selbig J,Liu J,Fernie A R,Sweetlove L J.The metabolic response of heterotrophic Arabidopsis cells to oxidative stress.Plant Physiol,2007,143:312-325.
[24]Umbach A L,Fiorani F,Siedow J N.Characterization of transformed Arabidopsis with altered alternative oxidase levels and analysis of effects on reactive oxygen species in tissue.Plant Physiol,2005,139:1806-1820.
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