期刊
NEW PHYTOLOGIST
卷 234, 期 5, 页码 1753-1769出版社
WILEY
DOI: 10.1111/nph.18096
关键词
bHLH transcription factors; Fe homeostasis; OsbHLH061; OsIRO2; OsIRO3; OsPRI1; rice; TOPLESS; TOPLESS-RELATED co-repressor proteins
资金
- National Natural Science Foundation of China [32172668, 31470347, 31770269]
- Michigan State University - Australian Research Council Centre of Excellence in Plant Energy Biology [CE140100008]
The study reveals that the bHLH transcription factor OsbHLH061 interacts with OsPRI1 to regulate iron homeostasis in rice, ensuring plants adapt to varying iron environments and maintain iron balance. OsbHLH061 knockout or overexpression lines alter iron accumulation in shoots, and the OsbHLH061-OsPRI1 complex recruits co-repressors to repress the expression of iron-related transcription factors OsIRO2 and OsIRO3.
As excess iron (Fe) is toxic, uptake of this essential micronutrient must be tightly controlled. Previous studies have shown that Oryza sativa (rice) POSITIVE REGULATOR OF IRON HOMEOSTASIS1 (OsPRI1) acts upstream of the iron-related transcription factor 2 (OsIRO2) and OsIRO3 to positively regulate root-to-shoot Fe translocation. However, as expression of OsPRI1 is constitutive it is unclear how the Fe-deficiency response is turned off to prevent toxicity when Fe is sufficient. The bHLH transcription factor OsbHLH061 interacts with OsPRI1, and this study used molecular, genetics, biochemical and physiological approaches to functionally characterise OsbHLH061 and how it affects Fe homeostasis. OsbHLH061 knockout or overexpression lines increase or decrease Fe accumulation in shoots respectively. Mechanistically, OsbHLH061 expression is upregulated by high Fe, and physically interacts with OsPRI1, the OsbHLH061-OsPRI1 complex recruits TOPLESS/TOPLESS-RELATED (OsTPL/TPR) co-repressors to repress OsIRO2 and OsIRO3 expression. The OsbHLH061 ethylene-responsive element-binding factor-associated amphiphilic repression (EAR) motif is required for this transcriptional repression activity. These results define a functional OsTPL/TPR-OsbHLH061-OsPRI1-OsIRO2/3 module that negatively controls long-distance transport of Fe in plants for adaptation to changing Fe environments and maintain Fe homeostasis in rice.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据