巨桉转录因子ZF-HD基因家族及其功能初步分析

Analysis of Transcription Factor ZF-HD Gene Family and Expression Pattern of Eucalyptus grandis

[目的]解析转录因子ZF-HD在桉树生长发育中的作用,进而深入了解其在桉树中如何发挥功能。[方法]在本研究中利用生物信息学鉴定巨桉ZF-HD基因家族成员,并对其染色体定位、理化性质、基因结构、蛋白保守结构域和表达模式进行分析。[结果]桉树中共发现10个基因家族成员,编码78~343个氨基酸,几乎所有成员都属于碱性蛋白质,主要定位于细胞核,且motif1在ZF-HD家族中非常保守,其启动子顺式作用元件主要为激素应答、生长发育和逆境应答等响应元件。ZF-HD基因家族成员在不同组织、不定根诱导和不定芽诱导过程中的表达分析表明,大多数家族成员在不同组织中存在着差异表达,且家族成员主要在顶端等初生生长阶段表达。且巨桉ZF-HD家族部分成员在不定根和不定芽诱导阶段表达量显著上升,亚细胞定位分析与预测结果相同。同时EgrZHD2定位于细胞核,且在茎尖的表达量较高,随着茎顶端向下其表达量显著下降。[结论]巨桉ZF-HD基因家族成员在桉树不定根和不定芽诱导等发育中起着重要的调控作用。EgrZHD2作为重要的转录因子作用于桉树的初生生长以及不定根诱导等生物学过程。

[Objective]In order to analyze the role of the transcription factor ZF-HD in the growth and development in Eucalyptus and to further understand its function,ZF-HD gene family in eucalyptus.[Method]In this study,bioinformatics was used to identify members of the E.grandis ZF-HD gene family,and their chromosomal location,physical and chemical properties,gene structure,protein conserved domains and expression patterns were analyzed.[Result]A total of 10 ZF-HD gene members were identified in E.grandis,which encoded 78-343 amino acids.Meanwhile,almost all genes were basic proteins which mainly located in the nucleus.Moreover,motif1 is very conserved in the ZF-HD family,and their cis-acting promoter elements mainly included hormone response,growth and development,and stress response elements.Furthermore,the expression analysis of ZF-HD gene in various tissues,adventitious roots and buds inducing process was analyzed.The results showed that most of the family members were differentially expressed in various tissues,which mainly acted in the downward direction of stem apex,Meanwhile,the expression levels of ZF-HD family members altered significantly during adventitious root and bud induction.EgrZHD2 expressed in higher level at the stem apex and decreased significantly with gradually increased secondary growth.And the further subcellular localization analysis showed EgrZHD2 localized in cell nucleus,which was consistent with predicted results.[Conclusion]The ZF-HD gene family members of Eucalyptus grandis play an important regulatory role in the development of adventitious roots and adventitious buds.EgrZHD2 acts as an important transcription factor in the biological processes of primary growth and adventitious root induction in Eucalyptus.