谷子SWI3基因鉴定及其在盐和干旱胁迫下的表达分析

Identification of SWI3 Genes from Foxtail Millet(Setaria italica L.)and Its Expression Analysis under Salt and Drought Stresses

SWI/SNF染色质重塑因子在植物的生长发育及逆境应答过程中起重要作用。本研究首先通过序列比对,从谷子基因组中鉴定出6个候选SiSWI3基因,分别命名为SiSWI3A、SiSWI3B、SiSWI3C1、SiSWI3C2、SiSWI3D1和SiSWI3D2。然后对上述基因的结构、编码蛋白、启动子元件、亚细胞定位等进行生物信息学分析和预测,结果表明:SiSWI3蛋白都含有SANT Motif,且亚细胞定位预测显示SiSWI3成员主要被定位在细胞核中;SiSWI3基因启动子区域含有大量与光响应、激素类应答、逆境应答、代谢调控等相关的顺式作用元件。最后采用实时荧光定量PCR(qRT-PCR)检测这些基因在谷子苗期盐胁迫和干旱胁迫下的表达量变化,检测结果表明:SiSWI3基因受盐和干旱不同程度的诱导,说明SiSWI3基因参与谷子苗期盐胁迫和干旱胁迫应答。本研究所得结论为进一步探究SiSWI3染色质重塑因子在抗逆作物谷子的逆境响应中的功能和机制奠定了基础。

SWI/SNF chromatin remodeling factors play important rolesin plant development and stress response.In this study,six candidate SWI3 genes were identified,namely SiSWI3A,SiSWI3B,SiSWI3C1,SiSWI3C2,SiSWI3D1,SiSWI3D2 from foxtail millet(Setaria italica L.)genome through sequence alignment.Bioinformatics methods were used to analyze the gene structure,protein,promoter sequence,and subcellular localization.The result showed that all six genes contained the conserved characteristic domains of SANT Motif,besides subcellular localization predictions showed that SiSWI3 members were mainly localized in nucleus.cis-elements analysis revealed that light,hormonal,stress,metabolism regulation and other related cis-elements were presented in the promoter region of the SiSWI3 genes.Real-time quantitative PCR(qRT-PCR)was used to detect the expression levels of SiSWI3 genes under different stresses at seedling stage,including salt and drought stress at last.Stress expression analysis showed that the expression levels of SiSWI3 genes were induced under the salt and drought stresses,indicating that five SiSWI3 genes involved in salt and drought stress re-sponse at the seedling stage.This study lays a foundation for further research on the function and mechanisms of SiSWI3 chromatin remodeling factors in the stress response of millet.