大白菜生长素受体基因家族生物信息学鉴定与表达分析

Genome-wide Identification and Expression Analysis of the Auxin Receptor Gene Family in Chinese Cabbage

【目的】对大白菜生长素受体BrTIR1/AFBs基因家族进行系统分析,为大白菜BrTIR1/AFBs基因家族的功能挖掘和性状遗传改良提供理论依据。【方法】利用生物信息学方法,分析大白菜生长素受体基因家族的进化关系、编码蛋白、保守结构域和顺式作用元件。基于NCBI转录组测序(RNA-sep)数据,分析BrTIR1/AFBs基因家族在大白菜不同组织中的表达模式以及在根肿病入侵条件下的表达情况。【结果】从大白菜基因组数据库中鉴定得到10个BrTIR1/AFBs基因。拟南芥、茎瘤芥和大豆生长素受体基因家族多序列比对以及系统进化树分析结果显示:BrTIR1/AFBs基因分为6个亚家族(TIR1、AFB1、AFB2、AFB3、AFB4和AFB5),处于同一亚族的基因具有相似的结构。染色体定位结果显示:BrTIR1/AFBs基因家族成员分布在除Chr5、Chr6和Chr10号染色体之外的7条染色体上,呈现出不均匀分布。顺式作用元件分析结果显示:所有的BrTIR1/AFBs基因家族成员都含有响应生长素、防御和逆境胁迫的作用元件,预示着这些基因可能参与相应的生物学过程。组织表达模式分析发现:10个BrTIR1/AFBs基因的转录本在6个组织中被检测到,且不同组织中的表达量存在明显差异。大白菜BrTIR1/AFBs基因家族成员在根肿病病原菌入侵时表达量发生显著变化。【结论】大白菜生长素受体BrTIR1/AFBs基因家族成员具有保守的基因结构和功能结构域,在大白菜不同组织中发挥着特异的功能,且在抵御病害和干旱等逆境中发挥重要作用。

[Purpose]To systematically analyze the auxin receptor BrTIR1/AFBs gene family in Chinese cabbage,to provide theoretical basis for the function mining and genetic improvement of BrTIR1/AFBs gene family in Chinese cabbage.[Method]Using bioinformatics methods,analyzing the relationship between Chinese cabbage auxin receptor gene family evolution,coding protein,conservative domain structure and function components.Based on NCBI transcriptome sequencing(RNA-sep)data,analyze BrTIR1/AFBs gene families in Chinese cabbage expression patterns of different organizations,and under the condition of root disease invasion of expression.[Results]Ten BrTIR1/AFBs genes were identified from Chinese cabbage genome database.Multiple sequence alignment and phylogenetic tree analysis of the auxin receptor gene families of Arabidopsis thaliana,Brassica juncea and soybean showed that the BrTIR1/AFBs genes were divided into 6 subfamilies(TIR1,AFB1,AFB2,AFB3,AFB4 and AFB5),and the genes in the same subfamily had similar structures.Chromosomal localization results showed that the BrTIR1/AFBs gene family members were distributed on 7 chromosomes except Chr5,Chr6 and Chr10,showing an uneven distribution.Cis-acting element analysis showed that all members of the BrTIR1/AFBs gene family contained functional elements in response to auxin,defense,and stress,suggesting that these genes may be involved in relevant biological processes.Tissue expression pattern analysis revealed that the transcripts of 10 BrTIR1/AFBs genes were detected in 6 tissues,and the expression levels were significantly different in different tissues.The expression levels of BrTIR1/AFBs gene family in Chinese cabbage were significantly changed when the pathogen of clubroot was invaded.[Conclusion]Auxin receptor BrTIR1/AFBs family of Chinese cabbage have conserved gene structure and functional domain,and play specific functions in different tissues of Chinese cabbage,and play an important role in resisting disease and drought.