海岛棉类受体胞质激酶RLCK VI家族全基因组鉴定与胁迫表达分析

Genome-wide Identification and Expressions under Stresses of RLCK VI Family in Gossypium barbadense

【目的】对海岛棉(Gossypium barbadense)类受体胞质激酶RLCK VI(GbRLCK VI)家族基因进行全基因组分析,为深入研究RLCK VI家族基因参与棉花生长发育和抗逆的调控机制提供参考。【方法】基于最新发布的海岛棉基因组数据,利用生物信息学手段对GbRLCK VI家族基因进行全基因组鉴定,并系统分析该家族基因成员的理化性质、序列特征、基因复制、系统进化和表达特征。【结果】海岛棉中共鉴定出39个GbRLCK VI家族基因,经聚类分析将其分为A、B两组,其中A组22个,B组17个,均含有1个激酶结构域,分布于16条染色体,多数位于质膜。基因复制分析表明,该家族在进化过程中发生染色体片段复制事件;Ka/Ks分析显示,所有基因对Ka/Ks均小于1,表明GbRLCK VI家族基因在进化过程中可能经历了严格的纯化选择作用。转录组分析表明,GbRLCK VI家族基因在10个不同组织中的表达模式不同,11个基因在花器官中优势表达,9个基因在根茎叶中优势表达;逆境胁迫下的表达分析显示,8个基因在干旱、盐、黄萎病胁迫下优势表达,4个基因只在黄萎病胁迫下优势表达,说明GbRLCKVI基因能快速地参与抗逆反应,挑选4个基因GB_A12G0061、GB_A11G2234、GB_D01G2010、GB_D03G0730进行qRT-PCR验证,表达分析结果显示,4个基因在干旱、盐或黄萎病菌胁迫下的表达趋势与转录组数据一致,表明它们参与了棉花对逆境胁迫(干旱、盐和黄萎病菌)的响应过程。【结论】明确了GbRLCK VI家族基因在基因组中的分布特征、结构特征以及系统进化特征,根据转录组数据初步揭示了该家族基因在棉花生长发育和抗逆胁迫中的功能。

【Objective】Genomes and expressions under stresses of the RLCK VI family genes in Gossypium barbadense were determined to study the regulatory mechanisms of the growth,development,and stress resistance of cotton plants.【Method】Based on the latest released data on G.barbadense genome,bioinformatics of GbRLCK VI was analyzed to understand the associated physiochemical properties,sequence characteristics,gene replication,phylogenetic evolution,and expression.【Result】Thirty-nine RLCK VI were identified in G.barbadense which were clustered into two categories of 22 in Group A and 17 in Group B.Both groups contained a kinase domain distributed in 16 chromosomes with most of them located in plasma membrane.The gene family had undergone chromosome fragment duplication events during evolution.Sinceall Ka/Ks of the gene pairs were less than 1,strict purification and selection might have taken place in the process.The expressions of GbRLCK VI as shown by the transcriptome analysis varied in 10 different tissues with 11 predominantly expressed in the floral organs,while 9 in the roots,stems,and leaves.Under different stresses,8 genes were significantly expressed by the imposed drought,salt,and verticillium wilt,and 4 only by verticillium wilt.On 4 selected genes,i.e.,GB_A12G0061,GB_A11G2234,GB_D01G2010,and GB_D03G0730,qRT-PCR showed their expressions under drought,salt,or verticillium wilt stress to agree with what the transcriptome data did.Their involvement in the stress response of the cotton plant was confirmed.【Conclusion】The genome,structure,and phylogenetic characteristics of GbRLCK VI family in G.barbadense were determined.Their roles in the growth,development,and stress responses of the cotton plant were clarified.