Combined metabolomic and transcriptomic analysis evidences the interaction between sugars and phosphate in rice

Area of Science:

• Plant Physiology
• Molecular Biology
• Biochemistry

Background:

• Phosphate (Pi) is an essential macronutrient for plant growth, but its availability is often limited in soil.
• Plants possess intricate regulatory mechanisms to enhance Pi acquisition and utilization under deficiency.
• Understanding these adaptive strategies is crucial for improving crop yields in nutrient-poor environments.

Purpose of the Study:

• To investigate the global metabolic and gene expression changes in rice in response to phosphate deficiency.
• To elucidate the interaction between sugar metabolism and phosphate homeostasis in rice.
• To determine the role of the OsPHR2 gene in mediating these responses.

Main Methods:

• Metabolomic and transcriptomic analyses were conducted on rice leaves and roots under Pi deficiency.
• Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was used to identify enriched pathways.
• Exogenous sugar supply experiments were performed to assess its effect on Pi starvation responses.

Main Results:

• Phosphate deficiency led to significant changes in 23 metabolites and 779 genes common to both rice leaves and roots.
• Accumulation of sucrose, trehalose, and melibiose was observed under Pi deficiency.
• Differentially expressed genes and accumulated metabolites were co-enriched in galactose metabolism pathways.
• Exogenous sugar supply induced Pi starvation responsiveness and the expression of OsPHR2.

Conclusions:

• A significant interaction exists between sugar metabolism and phosphate homeostasis in rice.
• The OsPHR2 gene plays a central role in regulating the plant's response to phosphate starvation.
• These findings provide insights into the complex regulatory network governing nutrient acquisition in plants.