谷子抗旱相关蛋白激酶基因家族鉴定及表达分析

Identification and expression of protein kinase gene family related to drought resistance in Setaria italica

[目的]蛋白激酶是一类催化蛋白质磷酸化反应的酶,普遍存在于植物体中,参与调控植物生长发育和抗逆等多种生理反应。本文旨在探究谷子响应干旱胁迫与蛋白激酶之间的关系,为谷子抗旱品种的培育提供参考。[方法]运用生物信息学方法,分析了谷子蛋白激酶基因家族的35个抗旱相关蛋白激酶基因的系统进化关系、基因结构、保守基序、保守结构域、启动子顺式元件以及在干旱处理下和不同组织中基因表达水平。[结果]这35个谷子抗旱相关蛋白激酶基因分布于8条染色体上,被分为4个亚家族;多数亲缘关系较近的基因,其外显子-内含子结构、保守基序、保守结构域也较为相似,它们可能具有功能上的相似性;启动子元件分析发现,多数基因启动子区含有ABA响应元件(ABRE)和干旱诱导响应元件(MBS);组织特异性表达发现,SiPK 20和SiPK 25基因表现出显著的组织特异性表达模式,SiPK 20在叶中表达量较高,SiPK 25在根中表达量较高;干旱诱导基因表达分析显示,在抗旱品种勾勾母鸡咀中,干旱处理后SiPK 1和SiPK 4基因表达量显著上升,并且SiPK 1、SiPK 4启动子区域都含有较多的MBS元件,说明SiPK 1和SiPK 4极有可能参与谷子干旱胁迫响应,并且SiPK 4在根中表达量较高。[结论]SiPK 4可能通过调控谷子根部发育参与根部对干旱胁迫的应答反应,可作为抗旱相关的候选基因。

[Objective]Protein kinases are a class of enzymes that catalyze the phosphorylation of proteins.They are ubiquitous in plants and involved in the regulation of various physiological responses such as plant growth and development and stress resistance.This study was aimed to explore the relationship between drought response and protein kinases in foxtail millet,and to provide reference for the breeding of foxtail millet drought-resistant varieties.[Methods]The phylogenetic relationship,gene structure,conserved motifs,conserved domains and promoter cis-elements of 35 drought resistance-related protein kinase genes in foxtail millet were analyzed using bioinformatics methods.Gene expression analyses were also carried out to determine gene reaction to drought treatment in different plant tissues.[Results]All 35 tested drought resistance-related protein kinase genes were distributed on 8 chromosomes and divided into 4 subfamilies.Most of closely related genes had similar exon-intron structure,conserved motifs and conserved domains,which indicated that they might possess functional similarities.Promoter cis-element analysis indicated that the promoter regions of most genes contained ABA response elements(ABRE)and drought-inducing response elements(MBS).Highly tissue-specific expression pattern was noticed for both SiPK 20 and SiPK 25 genes which were highly expressed in leaves and roots,respectively.Drought-inducing gene expression analysis demonstrated a significantly increased expression levels of SiPK 1 and SiPK 4 after drought treatment in the drought-resistant variety(GG),and the promoter regions of SiPK 1 and SiPK 4 contained more MBS elements,which indicated that SiPK1 and SiPK 4 were more likely to participate in drought stress response in foxtail millet.SiPK 4 was highly expressed in roots.[Conclusion]SiPK 4 might participate in root response to drought stress by regulating root development of foxtail millet,and could be used as a candidate gene to improve the drought resistance of crop.