Abstract: Verticillium wilt is known as cotton cancer. Identifying of disease resistance gene is the basis for cotton verticillium wilt resistant molecular breeding. WRKY transcription factors play important roles in regulating plant responses to various abiotic and biotic stresses. In this study, a WRKY transcription factor GbWRKY53 was cloned from sea island cotton Pima 90-53 with high resistance to verticillium wilt. Its open reading frame (ORF) was 999 bp, and encoded a putative WRKY group Ⅲ protein with 332 amino acids and contained one conserved WRKY domains and one HXC zinc finger structure. The gene structure analysis showed that GbWRKY53 contained 3 exons and 2 introns. Phylogenetic analysis showed that GbWRKY53 closed to GrWRKY53. The expression of GbWRKY53 gene increased firstly and then decreased, and the expression of 12 h was the highest after Verticillium dahliae treatment. The expression of GbWRKY53 increased significantly after SA induction for 8 h, and maintained at a high level to 24 h. After the induction of methyl jasmonate (MeJA), the expression of GbWRKY53 reached the maximum at 12 h and then decreased. The expression level of GbWRKY53 was significantly lower than that of salicylic acid at the same time. The expression of GbWRKY53 gene was only slightly increased after the induction of ACC. It could be concluded that GbWRKY53 gene involved in the complex plant signaling pathway, and played an important role in cotton stress response to Verticillium dahliae.

Key words: cotton, WRKY, verticillium wilt, gene clone, expression analysis

摘要： 黄萎病被称为棉花的“癌症”，挖掘和鉴定抗病相关基因是棉花抗黄萎病分子育种 的基础。WRKY转录因子在植物对生物和非生物胁迫应答过程中起重要调控作用。从 高抗黄萎病品种海岛棉Pima90-53中克隆了WRKY转录因子GbWRKY53，其开放阅读框 （open reading frame, ORF）为999 bp，编码332 个氨基酸，含有1 个WRKY结构 域及HXC型锌指结构，属于WRKY转录因子家族的第Ⅲ组。基因结构分析表明， GbWRKY53基因有3 个外显子和2 个内含子。系统进化分析表明，GbWRKY53与雷蒙德 氏棉（Gossypiumr aimindii）GrWRKY53的亲缘关系最近。当黄萎病菌诱导后， GbWRKY53基因表达量呈先增加后降低的变化趋势，处理后12 h其表达量达到最大； 水杨酸（SA）诱导后，GbWRKY53表达量在8 h明显增加，且一直持续增高到24 h； 而茉莉酸甲酯（MeJA）诱导后，GbWRKY53表达量在12 h达到最高值随后下降，且其 表达水平明显低于同时间水杨酸诱导后的表达量。1-氨基环丙烷-1-羧酸（ACC）诱 导后，GbWRKY53基因表达量仅微量上调。由此推断，GbWRKY53基因可能参与了复杂 的植物信号途径并在棉花抗黄萎病菌胁迫应答中起重要作用。

关键词: 棉花, WRKY, 黄萎病, 基因克隆, 表达分析