中国农业科学 ›› 2011, Vol. 44 ›› Issue (12): 2454-2461 .doi: 10.3864/j.issn.0578-1752.2011.12.006

• 植物保护 • 上一篇    下一篇

茉莉酸和真菌病原诱导的水稻WRKY30转录因子基因的分离及表达特征

彭喜旭; 胡耀军; 唐新科; 周平兰; 邓小波; 王海华
  

  1. 湖南科技大学生命科学学院
  • 收稿日期:2010-12-29 修回日期:2011-01-24 出版日期:2011-06-15 发布日期:2011-06-15
  • 通讯作者: 王海华

Isolation and Expression Profiles of Rice WRKY30 Induced by Jasmonic Acid Application and Fungal Pathogen Infection

PENG Xi-xu; HU Yao-jun; TANG Xin-ke; ZHOU Ping-lan; DENG Xiao-bo; WANG Hai-hua
  

  1. 湖南科技大学生命科学学院
  • Received:2010-12-29 Revised:2011-01-24 Online:2011-06-15 Published:2011-06-15

摘要:

【目的】分离水稻WRKY30,为阐明WRKY转录因子在水稻抗病反应中的调节作用提供依据,为抗病性的合理利用和品种遗传改良提供基因材料。【方法】采用RT-PCR获得包含最大开放阅读框(ORF)的WRKY30 cDNA序列,运用生物信息学手段进行序列分析,通过Southern杂交确定基因在基因组中的拷贝数,利用Northern分析或RT-PCR方法,研究基因的器官特异性表达和病原、激素以及非生物胁迫诱导表达的特征。【结果】 WRKY30 包含一个长2 022 bp的完整ORF,编码674个氨基酸,具有1个核定位信号和2个典型的WRKY保守结构域,锌指纹组成为C2H2,归类于WRKY第一组,与大麦、高粱和短柄草等单子叶植物WRKY的氨基酸序列同一性较高。WRKY30在基因组中以单拷贝存在,在茎、叶和颖果中表达丰度最高,根和穗中次之,花中最低。WRKY30受稻瘟菌和纹枯菌快速诱导。抗病相关信号分子水杨酸(SA)和茉莉酸甲酯(MeJA)也能诱导该基因表达迅速上调,而乙烯(ET)对其表达无明显影响,脱落酸抑制其表达。除伤引起WRKY30表达上调外,其它非生物胁迫如冷、高盐和干旱对其表达无明显影响。【结论】WRKY30可能参与水稻对稻瘟菌和纹枯菌防御反应的调控,这种调节作用依赖于SA和JA介导的信号途径,而与ET信号途径无关。

Abstract:

【Objective】The objective of this study is to isolate rice WRKY30 and provide not only a foundation for elucidating the roles of WRKY transcription factors in the regulation of defense responses in rice, but also gene sources for reasonable utilization of pathogen-resistance and genetic modification in rice breeding. 【Method】RT-PCR was used to amplify the full cDNA length of WRKY30 including its largest open reading frame (ORF). Bioinformatical tools were employed to analyze its sequence and coding protein. Copies of WRKY30 in the rice genome were determined by Southern hybridization, and the organ-specific expression characteristics and induced expression profiles under pathogen challenges, hormone treatments and abiotic stresses were investigated by Northern blot or RT-PCR. 【Result】The WRKY30 contained an entire ORF in length of 2 022 bp and was predicted to encode a protein of 674 amino acid residues consisting of two WRKY domains each with a zinc finger motif of C2H2 and a nuclear localization signal, belonging to the WRKY subgroup I. WRKY30 shared high amino acid sequence identity with those from monocots such as wheat (Hordeum vulgare), Sorghum bicolor and Brachypodium sylvaticum. WRKY30 exists as a single copy in the rice genome. The transcript levels of WRKY30 were relatively high in stem, leaf and grain, next were root and panicle, and the least was flower. WRKY30 was rapidly induced in response to challenges with Magnaporthe grisea and Rhizoctonia solani, and also induced by exogenous salicylic acid (SA) and methyl jasmonate (MeJA), two important defense-related hormones. However,ethephon (ET) exerted no obvious effects on its expression. By contrast, abscisic acid inhibited the transcription of WRKY30. On the hand, wounding lead to upregulation of WRKY30 transcription, whereas there were no significant effects on its expression subjected to other abiotic stresses such as cold, high salt and dehydration. 【Conclusion】WRKY30 may be involved in the regulation of rice defense responses to blast and sheath blight fungi through SAand JA, but not ET-dependent signaling pathways.