蒙古冰草肉桂醇脱氢酶基因序列鉴定及功能分析  

Sequence Identification and Functional Analysis of Cinnamyl Alcohol Dehydrogenase Gene from Agropyron mongolicum

作　　者：王贺萍 孙震 刘雨辰 苏彦龙 杜锦瑜 赵彦 赵竑博 王召明 苑峰 刘亚玲 吴振映[2,3,4] 何峰 付春祥 Heping Wang;Zhen Sun;Yuchen Liu;Yanlong Su;Jinyu Du;Yan Zhao;Hongbo Zhao;Zhaoming Wang;Feng Yuan;Yaling Liu;Zhenying Wu;Feng He;Chunxiang Fu(College of Horticulture,South China Agricultural University,Guangzhou 510642,China;Qingdao Institute of Bioenergy and Bioprocess Technology,Chinese Academy of Sciences,Qingdao 266101,China;Shandong Energy Institute,Qingdao 266101,China;Qingdao New Energy Shandong Laboratory,Qingdao 266101,China;Key Laboratory of Grassland Resources,Ministry of Education/Key Laboratory of Forage Cultivation,Processing and Efficient Utilization of Ministry of Agriculture and Rural Affairs/College of Grassland,Resource and Environmental Science,Inner Mongolia Agricultural University,Hohhot 010018,China;Key Laboratory of Forage Breeding and Seed Production in Inner Mongolia Autonomous Region,Hohhot 010018,China)

机构地区：[1]华南农业大学园艺学院,广州510642 [2]中国科学院青岛生物能源与过程研究所,青岛266101 [3]山东能源研究院,青岛266101 [4]青岛新能源山东省实验室,青岛266101 [5]内蒙古农业大学草原与资源环境学院/农业农村部饲草栽培、加工与高效利用重点实验室/草地资源教育部重点实验室,呼和浩特010018 [6]内蒙古自治区牧草育种与良种繁育重点实验室,呼和浩特010018

出　　处：《植物学报》2024年第2期204-216,共13页Chinese Bulletin of Botany

基　　金：内蒙古自治区种业科技创新重大示范工程“揭榜挂帅”项目(No.2022JBGS0014);中央引导地方科技发展资金(No.2022ZY006);呼和浩特市科技创新领域人才项目(“政产学研推用银”创新联合体项目)(No.2022RC-联合体-2);山东能源研究院科研创新基金(No.SEII202142)。

摘　　要：肉桂醇脱氢酶(CAD)作为植物次生代谢尤其是木质素生物合成过程的关键酶,在调控植物生长发育和抵御生物/非生物胁迫等过程中发挥关键作用。蒙古冰草(即沙芦草(Agropyron mongolicum))耐旱耐寒,在我国北方荒漠草原区域广泛分布。为探讨CAD基因在蒙古冰草木质素合成和非生物胁迫抗性中的作用,从蒙古冰草全长转录组数据中筛选并克隆到1个CAD基因,序列长度1083 bp,命名为AmCAD。该基因编码361个氨基酸残基,同源序列比对发现蛋白质序列保守区域含有2个Zn^(2+)结合基序和NADP(H)辅因子结合基序,属于典型的CAD蛋白,且三维结构与AtCAD5相似。AmCAD在茎秆中高表达,对AmCAD重组蛋白的酶学性质分析表明,该蛋白对不同肉桂醛类底物均具有很强的催化能力,其中对松柏醛和芥子醛的底物亲和力更强。用不同浓度甘露醇模拟干旱胁迫,蒙古冰草AmCAD基因表达受到显著诱导。研究结果表明,AmCAD在蒙古冰草木质素合成和干旱胁迫抗性中发挥重要作用,可为提高蒙古冰草品质和抗逆性分子育种提供有价值的基因资源。As an essential enzyme in plant secondary metabolism,cinnamyl alcohol dehydrogenase(CAD)plays a key role in regulating plant growth and development,as well as biological/abiotic stress resistance.Agropyron mongolicum is a traditional forage grass widely distributed in the desert grassland areas of northern China,which exhibited high tolerance to drought and cold stresses.To explore the role of cinnamyl alcohol dehydrogenase in A.mongolicum,in this study,a CAD gene was identified from the full-length transcriptome data of A.mongolicum and subsequentially analyzed in vitro.The 1083 bp coding sequence of AmCAD encodes 361 amino acids,which has typical conserved CAD region containing two Zn2+binding motifs and NADP(H)cofactor binding motifs,belongs to the typical CAD protein,and its three-dimensional structure is similar to AtCAD5.AmCAD is highly expressed in the stem.The AmCAD recombinant protein showed a robust catalytic ability to different cinnamaldehyde substrates,with the highest substrate affinity of coniferyl aldehyde and sinapaldehyde.Under drought stress condition,the expression level of AmCAD was significantly induced,indicating a potential function of this gene in stress tolerance.The experimental results indicate that AmCAD may play an important role in lignin biosynthesis and drought stress tolerance in A.mongolicum.Our research provided potentially valuable genetic resources for molecular breeding of A.mongolicum to improve biomass quality and stress resistance.

关 键 词：蒙古冰草 肉桂醇脱氢酶 木质素 抗旱性 

分 类 号：S543.9[农业科学—作物学]