Identification and expression analysis of WRKY transcription factor genes in response to fungal pathogen and hormone treatments in apple (Malus domestica)
Identification and expression analysis of WRKY transcription factor genes in response to fungal pathogen and hormone treatments in apple (Malus domestica)
复制标题
苹果响应真菌病原体和激素处理的 WRKY 转录因子基因的鉴定和表达分析
DOI：
10.1007/s12374-016-0577-3
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发表时间：
2017-04-01
影响因子：
2.9
通讯作者：
Wang, Sanhong
中科院分区：
文献类型：
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作者：
Lui, Shuai;Luo, Changguo;Wang, Sanhong
WRKY家族是高等植物中发现的一个大型转录因子家族，在生物过程和环境适应的许多方面起着核心作用。然而，在苹果（Malus domestica）中，关于这一科的资料很少。本研究共鉴定了苹果基因组中的119个WRKY候选基因，并根据保守域的结构将其划分为3个主要类群（Group I-III）。每个类群或亚类群具有相似的外显子-内含子结构和基序组成。进化分析表明，44个MdWRKY基因聚集在20个密集区域（<100 kb）， 78个MdWRKY基因形成85对共线关系，表明串联重复和片段重复在苹果WRKY基因家族的进化和多样化中发挥了重要作用。此外，利用RNA-seq和qRT-PCR检测了MdWRKY基因在生物胁迫（alternnaria alternia）和激素处理[水杨酸（SA）、茉莉酸甲酯（MeJA）和乙烯利]下在苹果叶片中的表达。结果表明，63个MdWRKY基因对苹果互花霉病原菌感染的转录本丰度存在差异表达。此外，在SA、MeJA或乙烯利植物生长调节剂处理下，苹果叶片中大多数病原菌应答基因MdWRKY也发生了显著变化，表明SA、JA与生物胁迫下的乙烯（Eth）激素信号相互作用。本研究可为今后WRKY基因在苹果抗病性方面的遗传修饰研究提供基础。
The WRKY family, a large family of transcription factors (TFs) found in higher plants, plays central roles in many aspects of biological processes and adaption to environment. However, little information is available on this family in apple (Malus domestica). In the present study, a total of 119 candidate WRKY genes in apple genome were identified and classified into three main groups (Group I–III) based on the structure of the conserved domains. Each group or subgroup showed similar exon–intron structures and motif compositions. The evolution analysis showed that 44 MdWRKY genes clustered into 20 intensive regions (<100 kb) and 78 MdWRKY formed 85 pairs of collinear relationships, suggesting that both tandem and segmental duplications played an important role in the evolution and diversification of the WRKY gene family in apple. Furthermore, the expression of the MdWRKY genes in apple leaves in response to biotic stress (Alternaria alternate) and hormone treatments [salicylic acid (SA), methyl jasmonate (MeJA) and ethephon] was examined by using RNA-seq and qRT-PCR. The results showed that 63 MdWRKY genes had differential expression in their transcript abundance in response to Alternaria alternata apple pathotype infection. Moreover, most pathogen responsive MdWRKY genes were also changed significantly when apple leaves were treated by SA, MeJA or ethephon plant growth regulations, suggesting an interaction between SA, JA and ethylene (Eth) hormone signaling under biotic stress. This work may provide the basis for future studies of the genetic modification of WRKY genes for pathogen resistance in apple.