GATA类转录因子在调控植物响应非生物胁迫中发挥重要作用.本研究从甘薯中克隆出 1 个IbGATA16 基因,对其进行生物信息学分析,并对 IbGATA16 基因在甘薯干旱和盐胁迫处理中的表达模式进行分析.结果表明:甘薯IbGATA16 基因CDS序列全长 420 bp,编码 139 个氨基酸,蛋白分子量为 15.39 kDa,等电点为 9.97;IbGATA16 基因组全长为 582 bp,包含 3 个外显子和 2 个内含子;IbGATA16 为不稳定的亲水性脂溶蛋白,亚细胞定位预测显示该蛋白定位于细胞核,具有C-X2-C-X17-C-X2-C结构域,属于典型的GATA类转录因子.IbGATA16 基因上游 1382 bp的启动子序列存在多种顺式作用元件,如MYB、ABRE、GARE-motif等.多重序列比对和系统进化树分析结果显示,IbGATA16蛋白与三裂叶薯ItGATA16 的亲缘关系最近,N端的锌指结构域序列高度一致,表明二者可能具有相似的功能.实时荧光定量结果表明,IbGATA16 在甘薯根、茎、叶片等组织中均有表达,在叶中的表达量显著高于茎与根的表达量.IbGATA16对干旱和盐胁迫显著诱导表达,在干旱和盐胁迫处理 0、1、3、6、12、24 h后,IbGATA16 的表达量均显著高于 0 h.干旱胁迫下,IbGATA16 的表达量在 1 h时达到峰值;在盐胁迫下,IbGATA16 的表达量在 3 h时达到最大值.以上结果表明,IbGATA16 基因参与了甘薯对干旱和盐胁迫的应答响应,在根、茎和叶中的调控存在差异.本研究为进一步揭示IbGATA16 在甘薯中抵御逆境胁迫的机理提供参考.
GATA transcription factors play an important role in regulating plant response to abiotic stress.In this study,an IbGATA16 gene was cloned from sweet potato and analyzed by bioinformatics.The expression pattern of IbGATA16 gene in sweet potato under drought and salt stress was analyzed.Experimental results show that the full length of Ib-GATA16 CDS sequence is 420 bp,and it encodes 139 amino acids.The molecular weight of IbGATA16 was 15.39 kDa,isoelectric point was 9.97.The full length of the genome is 582 bp,including 3 exons and 2 introns.IbGATA16 is an unstable hydrophilic lipid-soluble protein.,and its subcellular localization predicts that the protein is located in the nu-cleus.It has the C-X2-C-X17-C-X2-C domain and belongs to the typical GATA class of transcription factors.There are many cis-acting elements in the 1382 bp upstream promoter sequence of IbGATA16 gene,such as MYB,ABRE,and GARE-motif.The results of multiple sequence alignment and phylogenetic tree analysis showed that IbGATA16 protein was closely related to ItGATA16.The sequence of the N-terminal zinc finger domain is highly consistent,suggesting a possible similar function.The results of real-time fluorescence quantification showed that IbGATA16 was expressed in root,stem and leaf tissues of sweet potato,and the expression level of IbGATA16 in leaves was significantly higher than that in stem and root tissues.IbGATA16 was significantly induced by drought and salt stress,and after 0,1,3,6,12 and 24 h of drought and salt stress,the expression of IbGATA16 was significantly higher than that of 0 h.Under drought stress,the expression of IbGATA16 reached its peak at 1 h,and under salt stress,the expression of IbGATA16 reached the maximum at 3 h.IbGATA16 positively responds to drought and salt stress in sweet potato.These results indicated that IbGATA16 gene was involved in the response of sweet potato to drought and salt stress,and the regulation of Ib-GATA16 gene was different in roots,stems and leaves.This study provides a reference for further research on the bio-logical function of IbGATA16 and its mechanism in response to stress in sweet potato.