‘GDDH13’和‘山定子’WRKY基因家族生物信息学比较及MdWRKY基因家族表达分析

Comparison of WRKY Gene Family Bioinformatics in'GDDH13'and M.baccata and Expression Analysis of MdWRKY Gene Family

WRKY基因家族是植物中最大的转录因子家族之一,在植物生长发育和抵御逆境胁迫中发挥重要作用。‘山定子’是中国重要的野生苹果属抗性种质资源,抗寒能力强。本研究通过生物信息学方法,较全面的比较了‘山定子’和栽培苹果‘GDDH13’两份材料中的WRKY基因家族信息,结果显示:‘GDDH13’中WRKY基因数量比‘山定子’多7个,多出的7个WRKY基因分布在GroupⅠ和GroupⅢ两个亚组中;通过比较发现‘山定子’和‘GDDH13’中的WRKY结构域和基因结构在相近亚组内非常保守;发现‘山定子’的WRKY基因家族有更多的成员启动子区含有低温和干旱响应元件,这可能与‘山定子’抗逆性强有关;通过基因染色体位置和苹果基因组范围内对MdWRKY基因进行的同线分析表明串联重复和部分重复,可能在苹果WRKY基因家族的扩张和进化中发挥了重要的作用;通过器官特异性表达模式和果实发育过程表达分析,鉴定到MdWRKY64和MdWRKY67可能与苹果果实成熟密切相关;通过不定根发育过程的表达分析,筛选到8个MdWRKY基因可能参与苹果不定根的形成。本研究为苹果WRKY基因的进化提供了一些数据,并为苹果WRKY基因的功能鉴定提供了参考,进一步为苹果的分子育种提供了帮助。

As one of the largest transcriptional factor family in plants,WRKY gene family have been found to play important roles in various stresses.Malus baccata is a wild apple species that widely used as a rootstock and breeding resource because of its cold tolerance and disease resistance.In this study,we compared the WRKY gene family information between M.baccata and'GDDH13'by bioinformatics methods.The results showed that'GDDH13'had seven more WRKY genes than M.baccata,and the seven more WRKY genes were distributed in groupⅠand groupⅡ.In general,most of these WRKY in the same sub-clade exhibited similar gene structure,and conserved domain.We identified the number of WRKY genes contained cold responsive element was higher for M.baccata,implying the WRKY genes may contributed to the cold tolerance of M.baccata.Gene chromosomal location and synteny analysis of MdWRKY genes within the apple genome demonstrated that tandem and segmental duplications have likely played critical roles in the expansion and evolution of the WRKY gene family in apple.Expression profile analysis indicated that MdWRKY64 and MdWRKY67 might play a positive role in apple fruit ripening.What's more,8 MdWRKY genes were identified,which may play important roles in adventitious root formation.The findings from this study would not only beneficial to the functional analysis of apple WRKY gene,but also contribute to the molecular breeding of apple.