AUTHOR=Wang Fei , Wang Yan , Ying Luying , Lu Hong , Liu Yijian , Liu Yu , Xu Jiming , Wu Yunrong , Mo Xiaorong , Wu Zhongchang , Mao Chuanzao 

TITLE=Integrated transcriptomic analysis identifies coordinated responses to nitrogen and phosphate deficiency in rice

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1164441

DOI=10.3389/fpls.2023.1164441

ISSN=1664-462X

ABSTRACT=<p>Nitrogen (N) and phosphorus (P) are two primary components of fertilizers for crop production. Coordinated acquisition and utilization of N and P are crucial for plants to achieve nutrient balance and optimal growth in a changing rhizospheric nutrient environment. However, little is known about how N and P signaling pathways are integrated. We performed transcriptomic analyses and physiological experiments to explore gene expression profiles and physiological homeostasis in the response of rice (<italic>Oryza sativa</italic>) to N and P deficiency. We revealed that N and P shortage inhibit rice growth and uptake of other nutrients. Gene Ontology (GO) analysis of differentially expressed genes (DEGs) suggested that N and Pi deficiency stimulate specific different physiological reactions and also some same physiological processes in rice. We established the transcriptional regulatory network between N and P signaling pathways based on all DEGs. We determined that the transcript levels of 763 core genes changed under both N or P starvation conditions. Among these core genes, we focused on the transcription factor gene <italic>NITRATE-INDUCIBLE, GARP-TYPE TRANSCRIPTIONAL REPRESSOR 1</italic> (<italic>NIGT1</italic>) and show that its encoded protein is a positive regulator of P homeostasis and a negative regulator of N acquisition in rice. NIGT1 promoted Pi uptake but inhibited N absorption, induced the expression of Pi responsive genes <italic>PT2</italic> and <italic>SPX1</italic> and repressed the N responsive genes <italic>NLP1</italic> and <italic>NRT2.1</italic>. These results provide new clues about the mechanisms underlying the interaction between plant N and P starvation responses.</p>