A reciprocal inhibitory module for Pi and iron signaling

• 作者: Meina Guo Wenyuan Ruan Yibo Zhang Yuxin Zhang Xueqing Wang Zhenhui Guo Long Wang Tian Zhou Javier Paz-Ares Keke Yi
• 来源期刊: 分子植物（英文版）
• 年，卷（期）: 2022,（1）
• 所属期刊栏目: Research Articles
• 页码范围: 138-150
• 页数: 13页
• 语种: 英文

摘要

Phosphorous (P) and iron (Fe),two essential nutrients for plant growth and development,are highly abundant elements in the earth's crust but often display low availability to plants.Due to the ability to form insoluble complexes,the antagonistic interaction between P and Fe nutrition in plants has been noticed for decades.However,the underlying molecular mechanism modulating the signaling and homeostasis between them re-mains obscure.Here,we show that the possible iron sensors HRZs,the iron deficiency-induced E3 ligases,could interact with the central regulator of phosphate (Pi) signaling,PHR2,and prompt its ubiquitination at lysine residues K319 and K328,leading to its degradation in rice.Consistent with this,the hrzs mutants dis-played a high Pi accumulation phenotype.Furthermore,we found that iron deficiency could attenuate Pi star-vation signaling by inducing the expression of HRZs,which in turn trigger PHR2 protein degradation.Inter-estingly,on the other hand,rice PHRs could negatively regulate the expression of HRZs to modulate iron deficiency responses.Therefore,PHR2 and HRZs form a reciprocal inhibitory module to coordinate Pi and iron signaling and homeostasis in rice.Taken together,our results uncover a molecular link between Pi and iron master regulators,which fine-tunes plant adaptation to Pi and iron availability in rice.