論文

査読有り
2013年10月

Genome-wide identification of WRKY45-regulated genes that mediate benzothiadiazole-induced defense responses in rice

BMC PLANT BIOLOGY
  • Akira Nakayama
  • ,
  • Setsuko Fukushima
  • ,
  • Shingo Goto
  • ,
  • Akane Matsushita
  • ,
  • Masaki Shimono
  • ,
  • Shoji Sugano
  • ,
  • Chang-Jie Jiang
  • ,
  • Aya Akagi
  • ,
  • Muneo Yamazaki
  • ,
  • Haruhiko Inoue
  • ,
  • Hiroshi Takatsuji

13
開始ページ
終了ページ
150
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1186/1471-2229-13-150
出版者・発行元
BIOMED CENTRAL LTD

Background: The rice transcription factor WRKY45 plays a crucial role in salicylic acid (SA)/benzothiadiazole (BTH)-induced disease resistance. Its knockdown severely reduces BTH-induced resistance to the fungal pathogen Magnaporthe oryzae and the bacterial pathogen Xanthomonas oryzae pv. oryzae (Xoo). Conversely, overexpression of WRKY45 induces extremely strong resistance to both of these pathogens. To elucidate the molecular basis of WRKY45-dependent disease resistance, we analyzed WRKY45-regulated gene expression using rice transformants and a transient gene expression system.
Results: We conducted a microarray analysis using WRKY45-knockdown (WRKY45-kd) rice plants, and identified WRKY45-dependent genes among the BTH-responsive genes. The BTH-responsiveness of 260 genes was dependent on WRKY45. Among these, 220 genes (85%), many of which encoded PR proteins and proteins associated with secondary metabolism, were upregulated by BTH. Only a small portion of these genes overlapped with those regulated by OsNPR1/NH1, supporting the idea that the rice SA pathway branches into WRKY45-regulated and OsNPR1/NH1-regulated subpathways. Dexamethazone-induced expression of myc-tagged WRKY45 in rice immediately upregulated transcription of endogenous WRKY45 and genes encoding the transcription factors WRKY62, OsNAC4, and HSF1, all of which have been reported to have defense-related functions. This was followed by upregulation of defense genes encoding PR proteins and secondary metabolic enzymes. Many of these genes were also induced after M. oryzae infection. Their temporal transcription patterns were consistent with those after dexamethazone-induced WRKY45 expression. In a transient expression system consisting of particle bombardment of rice coleoptiles, WRKY45 acted as an effector to trans-activate reporter genes in which the luciferase coding sequence was fused to upstream and intragenic sequences of WRKY62 and OsNAC4. Trans-activation of transcription occurred through a W-box-containing sequence upstream of OsNAC4 and mutations in the W-boxes abolished the trans-activation.
Conclusions: These data suggest a role of WRKY45 in BTH-induced disease resistance as a master regulator of the transcriptional cascade regulating defense responses in one of two branches in the rice SA pathway.

Web of Science ® 被引用回数 : 47

リンク情報
DOI
https://doi.org/10.1186/1471-2229-13-150
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000326224000002&DestApp=WOS_CPL
ID情報
  • DOI : 10.1186/1471-2229-13-150
  • ISSN : 1471-2229
  • Web of Science ID : WOS:000326224000002

エクスポート
BibTeX RIS