杨树脯氨酸合成关键基因PagP5CS1全长克隆及功能验证  

Full-Length Cloning and Functional Berification of PagP5CS1 From Populus alba×P.glandulosa

作　　者：任若寒 王海泽 吴承生 衡启蒙 陈文义 孙甜甜 张丽娟 贺浩冉 李想 张银燕 樊军锋[1] 张一[1] REN Ruo-han;WANG Hai-ze;WU Cheng-sheng;HENG Qi-meng;CHEN Wen-yi;SUN Tian-tian;ZHANG Li-juan;HE Hao-ran;LI Xiang;ZHANG Yin-yan;FAN Jun-feng;ZHANG Yi(College of Forestry,Key Laboratory of Tree Cultivation on Loess Plateau,National Forestry and Grassland Administration,Northwest A&F University,Yangling 712100,Shaanxi,China;Shaanxi Ankang Forestry Technology Extension Center,Ankang 725000,Shannxi,China;Ganzhou City,Jiangxi Province Chongyi County Bureau of Agriculture and Rural affairs,Ganzhou 341399,Jiangxi,China)

机构地区：[1]西北农林科技大学林学院,国家林业和草原局黄土高原林木培育重点实验室,陕西杨陵712100 [2]陕西省安康市林业技术推广中心,陕西安康725000 [3]江西省赣州市崇义县农业农村局,江西赣州341399

出　　处：《西北林学院学报》2023年第4期90-96,共7页Journal of Northwest Forestry University

基　　金：国家自然科学基金(32171823)。

摘　　要：杨树是重要的工业用材树种。我国北方干旱和半干旱地区水分匮乏,干旱已成为影响杨树人工林可持续发展的一个重要因素。游离脯氨酸的积累常常在植物应对干旱等渗透胁迫时出现,以缓解干旱胁迫带给植物的损害。P5CS作为编码脯氨酸合成关键酶的基因,对于植物调控游离脯氨酸合成、增强耐干旱能力非常关键。该研究克隆84K杨脯氨酸合成代谢的关键基因PagP5CS1并在银中杨内进行遗传转化,从表型、分子和生理水平上对PagP5CS1转基因杨树株系进行了功能鉴定。本研究构建的PagP5CS1超表达载体通过叶盘法转化至银中杨叶片,成功获得12个PagP5CS1超表达杨树株系,其中P5CS1基因表达量最高的转基因株系为野生型表达量的8.3倍。经过干旱胁迫处理,相对于野生型,超表达株系叶片萎蔫程度更低;在干旱胁迫下,超表达株系中P5CS1基因表达量和脯氨酸含量均高于野生型,说明P5CS1超表达增强了杨树的耐旱性,P5CS1基因在干旱胁迫下发挥了正向调控作用。综上所述,杨树P5CS1基因对干旱胁迫高度响应,PagP5CS1超表达杨树会通过增加脯氨酸积累来增强杨树的耐旱性。Poplar(Populus)is an important timber production species for industry.Drought has become an important factor affecting the sustainable development of poplar plantations in arid and semi-arid areas in Northern China.Under osmotic stress,such as drought,plants often accumulate free proline to alleviate the damage caused by stress.P5CS,a gene encoding a key enzyme of proline synthesis,plays an important role in regulating free proline synthesis and enhancing drought tolerance in plants.In this study,PagP5CS1,a key gene of proline biosyhthesis,was cloned from P.alba×P.glandulosa and transformed into P.alba×P.berolinensis,and the function of PagP5CS1 transgenic poplar was identified from phenotypic,molecular and physiological levels.The constructed PagP5CS1 overexpression vector was transformed into P.alba×P.berolinensis by leaf disk method,and 12 poplar lines with PagP5CS1 overexpression were successfully obtained,among which the transgenic line with the highest expression level was 8.3 times that of the wild type.Compared with the wild type,leaf wilting degree of overexpression lines was lower after drought stress treatment.Under drought stress,the gene expression level of P5CS1 and proline content in the overexpression lines were higher than those in the wild type,indicating that the overexpression of P5CS1 enhanced the drought tolerance of poplar,and P5CS1 played a positive regulatory role.In conclusion,P5CS1 of poplar is highly responsive to drought stress,and PagP5CS1 overexpression poplar can enhance drought tolerance by increasing proline accumulation.

关 键 词：杨树 脯氨酸 P5CS1 干旱 

分 类 号：S792.11[农业科学—林木遗传育种]