龙眼DlWRKY52基因克隆及表达分析

WRKY转录因子在植物的生长发育和逆境胁迫响应中起着重要作用。前期研究发现,部分WRKY基因（比如DlWRKY52）参与了龙眼的成花诱导和逆境胁迫响应过程。为进一步研究龙眼WRKY基因的功能,以‘四季蜜’龙眼叶片cDNA为模板克隆得到DlWRKY52基因,并对其序列特征、组织表达模式、花果发育过程表达模式及亚细胞定位进行研究。结果表明：DlWRKY52基因的开放阅读框（open reading frame, ORF）全长为918 bp,编码306个氨基酸,具有典型的WRKY结构域和锌指结构,属于Ⅱc型WRKY蛋白。qRT-PCR结果表明,DlWRKY52基因在叶片、茎和果实器官中高表达;在花后80 d的果肉中显著上调表达;特异在‘四季蜜’成花诱导中下调表达。拟南芥原生质体瞬时表达结果显示,荧光信号主要集中在细胞核。上述结果表明,作为典型的转录因子,DlWRKY52编码的蛋白定位于细胞核。DlWRKY52可能参与了龙眼成花诱导及果实早期发育调控。

Clonging and Expression Analysis of WRKY52 Gene in Dimocarpus longan

WRKY transcription factors plays an important role in plant growth, development and stress response. Based on a previous study, we found several WRKY genes, such as DlWRKY52, were participated in the process of floral induction and stress response. To further reveal the function of longan WRKY genes, DlWRKY52 was cloned using the leave cDNA of ‘Sijimi’ longan as the template. Meanwhile, the sequence characteristics, tissue expression patterns, flower and fruit development process expression patterns and subcellular localization were also studied. Bioinformatics analysis indicated that the complete open reading frame (ORF) box of DlWRKY52 was 918 bp, encoding 305 amino acid residues. The amino acid sequence alignment analysis showed that DlWRKY52 contained a typical WRKY domain and a zinc finger structure, belonging to Group Ⅱc. The result of qRT-PCR showed that DlWRKY52 was highly expressed in leave, stem and fruit organs, significantly up-regualted in the pulp 80 days post-anthesis. The transient expression of Arabidopsis protoplasts demonstrated that DlWRKY52 protein was localized to the nucleus, indicating that DlWRKY52, as a typical transcription factor, is localized to the nucleus, and might participate in the regulating of longan floral induction and early fruit development.