紫花苜蓿CAX基因家族鉴定及其对非生物胁迫的响应分析  

Identification of CAX gene family and expression profile analysis of response to abiotic stress in alfalfa

作　　者：张国香 郭卫冷 毕铭钰 张力爽 王丹[1] 郭长虹[1] ZHANG Guo-xiang;GUO Wei-leng;BI Ming-yu;ZHANG Li-shuang;WANG Dan;GUO Chang-hong(Key Laboratory of Molecular Cytogenetics and Genetic Breeding of Heilongjiang Province,College of Life Science and Technology,Harbin Normal University,Harbin 150000,China)

机构地区：[1]黑龙江省分子细胞遗传与遗传育种重点实验室,哈尔滨师范大学生命科学与技术学院,黑龙江哈尔滨150000

出　　处：《草业学报》2022年第12期106-117,共12页Acta Prataculturae Sinica

基　　金：国家自然科学基金项目(31770575,U21A20182);黑龙江省自然科学基金优青项目(YQ2020C033);哈尔滨师范大学研究生创新基金(HSDSSCX2021-04)资助。

摘　　要：Ca^(2+)/H+反向转运蛋白(CAX)是一类重要的跨膜转运蛋白,在调控植物Ca^(2+)平衡、抵抗非生物胁迫和转运重金属离子等方面具有重要作用。利用生物信息学方法在全基因组水平对紫花苜蓿CAX基因家族进行了鉴定,并对其理化性质、结构特征、系统进化关系、顺式作用元件、染色体定位等进行了分析。结果表明,在紫花苜蓿全基因组中共筛选鉴定出15个MsCAX基因,分布于紫花苜蓿15条染色体上,发生22对基因片段重复事件,编码367~460个氨基酸,等电点为5。2~6。5,且均表现为疏水性蛋白。系统进化关系分析结果表明,MsCAXs分为2个亚家族,同一亚家族成员具有相似的基因结构、保守基序和跨膜结构域数量。MsCAXs启动子区域存在光响应性、激素反应性和胁迫响应元件。利用qRT-PCR分析了6个MsCAXs基因在非生物胁迫下的表达模式,结果表明,在干旱和低温胁迫下,6个MsCAX基因均显著下调表达,在盐和盐碱胁迫下,3个MsCAX基因上调表达。说明在不同的非生物胁迫下,MsCAXs基因表现出不同的表达模式。研究结果为进一步探索紫花苜蓿CAX基因家族的功能提供了参考。Ca^(2+)/H+reverse transporter proteins(CAX)are an important group of transmembrane transporters,which plays important roles in regulating Ca^(2+)balance,resisting abiotic stresses and transporting heavy metal ions in plants.Using bioinformatics methods,we performed a genome-wide identification of CAX gene family occurrence in alfalfa.In this work,the physicochemical properties,structural characteristics,phylogenetic relationships,cis-acting elements and chromosome locations of CAX gene family members were analyzed.Fifteen MsCAX genes were identified and these were distributed on 15 alfalfa chromosomes with 22 pairs of segmental duplication events.Further analysis showed that they encoded 367-460 amino acids with isoelectric points ranging from pH 5.2 to 6.5.All of them were hydrophobic proteins.Phylogenetic analysis showed that MsCAXs were divided into two subfamilies,and members of the same subfamily had similar genetic structures,conserved motifs,and the number of transmembrane domains.The promoter region of MsCAXs contained the light,hormone and stress-responsive elements.The expression patterns of six MsCAXs genes in response to abiotic stress were analyzed by qRT-PCR.It was found that all six MsCAX genes were significantly down-regulated under drought and low temperature stress,and three MsCAX genes were up-regulated under salt and saline-alkali stress.These results indicate that MsCAX gene has different expression patterns under different abiotic stresses.The results provide a reference for further exploration of the functions of the MsCAX gene family.

关 键 词：紫花苜蓿 CAX基因家族 全基因组 非生物胁迫 基因表达 

分 类 号：S541.9[农业科学—作物学]