毛果杨ZHD家族全基因组水平鉴定及在干旱胁迫下的表达分析

  目的  对毛果杨Populus trichocarpa ZHD (PtrZHD)家族进行生物信息学以及干旱胁迫下表达特性分析，为研究PtrZHD在干旱胁迫中的功能提供参考。  方法  利用生物信息学方法从全基因组水平鉴定出毛果杨ZHD家族全部成员，并对其进化、理化性质、基因结构、保守基序、启动子顺式作用元件和表达特性进行分析。  结果  毛果杨ZHD家族包括21个成员，可分为7个亚家族；有8对同源基因，且非同义替换率(K_a)/同义替换率(K_s)值远小于1。该家族成员理化性质存在差异，但其结构较为保守，均含有Motif 1；启动子区含有数量不等的激素和非生物胁迫响应元件，不同基因之间响应元件的种类存在差异。在毛果杨PtrZHDs中，分别有1、7和13个基因在根、茎和叶组织中具有偏好性表达特征；PtrZHD家族成员对干旱胁迫的响应具有组织和时间表达特异性，在根、茎和叶部组织中各成员的表达量不同，但随着干旱胁迫时间的增加均呈先上升后下降的趋势。  结论  PtrZHD家族基因对干旱胁迫有不同程度的响应，可调控毛果杨对干旱胁迫的应答。图6表2参27

Genome-wide identification of ZHD gene family of Populus trichocarpa and its expression under drought stress

  Objective  With an investigation of the bioinformatics information of the ZHD gene family of Populus trichocarpa (PtrZHD) and an analysis of the expression characteristics of this gene family under drought stress, This study is aimed to provide reference for exploring the functions of PtrZHD in drought stress.   Method  Bioinformatics was used to identify all members of the ZHD gene family in P. trichocarpa at the genome-wide level before an analysis was conducted of their evolution, physicochemical properties, gene structure, conserved Motifs, cis-acting elements of the promoter and expression characteristics.   Result  The ZHD gene family of P. trichocarpa consisted of 21 members, which could be divided into 7 subfamilies. There were 8 pairs of homologous genes in the ZHD gene family of P. trichocarpa, and the K_a/K_s value of each pair of homologous genes was far lower than 1. Though with different physicochemical properties, PtrZHD gene family members had relatively conservative structures, all containing Motif 1. Different numbers of hormone and abiotic stress response elements were found in the promoter regions of PtrZHD gene family members with various response elements among different genes. One, seven and thirteen members of the PtrZHDs gene family were preferentially expressed in the root, stem and leaf tissues of P. trichocarpa, respectively. The response of PtrZHD gene family members to drought stress was tissue-specific and time-specific with the expression levels of each member of ZHD gene family being different in root, stem and leaf tissues, yet with the increase of drought stress time, they all showed a trend of first increasing and then decreasing.   Conclusion  Different members of the PtrZHD gene family had different responses to drought stress, indicating that they might regulate the response of P. trichocarpa to drought stress. Ch, 6 fig. 2 tab. 27 ref.]