普通小麦JAZ基因家族鉴定及其响应冻害时基因差异表达和DNA变异分析

Identification of JAZ gene family and analysis on their differential expression under freezing stress and DNA variation in common wheat

茉莉酸(JA)途径参与小麦(Triticum aestivum)响应冰点以下低温胁迫,可以缓解冻害及其造成的减产。利用小麦基因组数据库筛选鉴定到63个TaJAZ基因,并通过生物信息学和分子生物学实验分析该家族基因结构特征、理化性质、时空表达模式及DNA变异。结果表明,TaJAZ基因不均匀分布在15条染色体上。系统发育分析表明,TaJAZ基因家族可分为10个亚群,且与大麦(Hordeum vulgare)的JAZ基因亲缘关系较近。进化选择分析表明,TaJAZ基因受到纯化选择。结合已有转录组数据分析TaJAZ在不同时期及冻害下表达模式,发现部分成员在小麦旗叶表达水平较高或在茎基部的表达量增加。TaJAZ-2A在茎、叶中的表达水平较高,且在抗寒品种‘京核1号’和较敏感品种‘淮麦18’中的表达上调,并检测到TaJAZ1-2A、TaJAZ6-4B和TaJAZ7-4B的非同义单核苷酸多态性(SNP)变异。本研究明确了TaJAZ基因家族的基因结构、进化、冻害下的表达,为深入研究TaJAZ基因功能及JA信号分子调控机制提供参考。

Jasmonic acid(JA)pathway is involved in the response of wheat(Triticum aestivum)to freezing stress,which can alleviate freezing injury and its yield reduction.Sixty-three Ta JAZ genes were identified from wheat genome databases.Structural characteristics,physicochemical properties,spatiotemporal expression patterns and DNA variations of the family genes were analyzed by bioinformatics and molecular biology experiments.The results show that TaJAZ members were unevenly distributed on 15 chromosomes.Phylogenetic analysis showed that the TaJAZ gene family is divided into 10 subgroups,among which TaJAZ genes and barley(Borbum vulgare)JAZ genes were closely related.The analysis of evolutionary selection showed that TaJAZ genes were subjected to purifying.Combined with the existing transcriptome data,the expression patterns in different periods and under freezing stress were analyzed,and the expression levels of some members were higher at flag leaf or increased at stem base.The expression levels of TAJAZ1-2A were higher in stem and leaf,and those of‘Jinghe 1’,which is freezing-resistant,was up-regulated compared with‘Huaimai 18’,which is sensitive.Non-synonymous single-nucleotide polymorphism(SNP)variation was found in TaJAZ1-2A,TaJAZ6-4B and TaJAZ7-4B.This study clarified the gene structure,evolution,and expression of TaJAZ gene family under freezing injury,and established base to further study the function of TaJAZ gene and the regulatory mechanism of JA signaling molecules.