An R2R3 MYB transcription factor in wheat, TaPIMP1, mediates host resistance to Bipolaris sorokiniana and drought stresses through regulation of defense- and stress-related genes

作者：Zhang, Zengyan^*; Liu, Xin; Wang, Xindong; Zhou, Miaoping; Zhou, Xianyao; Ye, Xingguo; Wei, Xuening

来源：NEW PHYTOLOGIST, 2012, 196(4): 1155-1170.

DOI：10.1111/j.1469-8137.2012.04353.x

• Bipolaris sorokiniana
• common wheat
• drought
• MYB transcription factor
• resistant response
• Triticum aestivum

In this study, we report new insights into the function of a wheat (Triticum aestivum) MYB gene TaPIMP1 through overexpression and underexpression, and its underlying mechanism in wheat.
Electrophoretic mobility shift and yeast-one-hybrid assays indicated that TaPIMP1 can bind to five MYB-binding sites including ACI, and activate the expression of the genes with the cis-element, confirming that TaPIMP1 is an MYB transcription activator.
TaPIMP1-overexpressing transgenic wheat exhibited significantly enhanced resistance to the fungal pathogen Bipolaris sorokiniana and drought stresses, whereas TaPIMP1-underexpressing transgenic wheat showed more susceptibility to the stresses compared with untransformed wheat, revealing that TaPIMP1 positively modulates host-defense responses to B. sorokiniana and drought stresses. Microarray analysis showed that a subset of defense- and stress-related genes were up-regulated by TaPIMP1. These genes, including TaPIMP1, RD22, TLP4 and PR1a, were regulated by ABA and salicylic acid (SA). TaPIMP1-underexpressing transgenic wheat showed compromised induction of these stress-responsive genes following ABA and SA treatments.
In summary, TaPIMP1, as a positive molecular linker, mediates resistance to B. sorokiniana and drought stresses by regulation of stress-related genes in ABA- and SA-signaling pathways in wheat. Furthermore, TaPIMP1 may provide a transgenic tool for engineering multiple-resistance wheat in breeding programs.

• 出版日期2012-12
• 单位江苏省农业科学院; 中国农业科学院