OsRIBONUCLEASE1-induced rRNA breakdown enhances rice root growth and phosphate use efficiency

Area of Science:

• Plant Biology
• Molecular Genetics
• Agricultural Science

Background:

• Phosphorus (P) management is crucial for crop yield, but improving P use efficiency (PUE) in rice remains a challenge.
• Understanding the molecular basis of PUE is essential for developing enhanced crop varieties.

Purpose of the Study:

• To investigate the role of the rice ribonuclease 1 (OsRNS1) gene in phosphorus deficiency tolerance and PUE.
• To elucidate the molecular mechanisms by which OsRNS1 influences P homeostasis in rice.

Main Methods:

• Overexpression and knockout of the OsRNS1 gene in rice.
• Localization studies of the OsRNS1 protein using GFP and GUS assays.
• Analysis of ribosomal RNA (rRNA) degradation and expression of related genes under P deficiency.

Main Results:

• OsRNS1 expression is induced by P deficiency and the protein localizes to the cell wall and endoplasmic reticulum.
• OsRNS1 overexpression enhances rRNA degradation and PUE, while its knockout reduces rRNA degradation.
• OsRNS1 overexpression improves tolerance to P-deficiency stress and influences the expression of acid phosphatase and phosphate transporter genes.

Conclusions:

• OsRNS1, a P deficiency-induced ribonuclease, plays a key role in regulating P homeostasis through rRNA degradation.
• The OsRNS1-mediated pathway provides a promising target for biotechnological development of rice with enhanced PUE.