OsCBL1 modulates rice nitrogen use efficiency via negative regulation of OsNRT2.2 by OsCCA1.

Background: For cereal crop breeding, it is meaningful to improve utilization efficiency (NUE) under low nitrogen (LN) levels while maintaining crop yield. OsCBL1-knockdown (OsCBL1-KD) plants exhibited increased nitrogen accumulation and NUE in the field of low N level.

Results: OsCBL1-knockdown (OsCBL1-KD) in rice increased the expression of a nitrate transporter gene OsNRT2.

OsCBL1 affects rice seedling growth by modulating nitrate and phosphate responses.

To sustain high crop yield, a comprehensive understanding of the processes by which plants sense and acquire nutrients is of great importance. For the efficiency of crop fertilizer, it is essential to exploring the the signaling networks that coordinate the usage of nitrogen and phosphorus, the most demanding two mineral nutrients in plants. Here, we found that a protein OsCBL1 (Calcineurin B-like protein 1) is involved in the regulation of nitrogen and phosphorus signaling in rice.