Related Experiment Video
Updated: Jul 11, 2025
08:46
Forward Genetic Screen Using Transgenic Calcium Reporter Aequorin to Identify Novel Targets in Calcium Signaling
Published on: August 1, 2020
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TORC pathway intersects with a calcium sensor kinase network to regulate potassium sensing in Arabidopsis
Kun-Lun Li1, Hui Xue1, Ren-Jie Tang1
1Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720.
Summary
Plants adapt to varying potassium (K) levels through a nutrient-sensing pathway. The target of rapamycin (TOR) complex and calcineurin B-like protein (CBL)-interacting kinase (CIPK) network reciprocally regulate K nutrient responses for optimal plant growth.
Area of Science:
- Plant Biology
- Molecular Biology
- Nutrient Signaling
Background:
- Potassium (K) is crucial for plant development, but its soil availability fluctuates.
- Plants must possess mechanisms to adapt to varying K nutrient levels for survival and growth.
Purpose of the Study:
- To elucidate the molecular mechanisms underlying plant adaptation to K nutrient status.
- To investigate the role of the target of rapamycin (TOR) pathway in K response.
Main Methods:
- Correlating plant growth rate with K availability in the growth medium.
- Investigating the interaction between the TOR complex (TORC) and the CBL-CIPK signaling network.
- Analyzing the phosphorylation of regulatory-associated protein of TOR (RAPTOR) by CIPKs.
Main Results:
- Plant growth rate is directly correlated with K availability, mediated by TOR.
- TORC and the CBL-CIPK pathway exhibit reciprocal regulation in response to K levels.
- High K activates TORC, suppressing the CBL-CIPK pathway via RAPTOR-CIPK interaction.
- Low K activates CBL-CIPK, inhibiting TORC through RAPTOR phosphorylation and TORC inactivation.
Conclusions:
- The TORC and CBL-CIPK modules form a regulatory network that orchestrates plant adaptation to environmental K fluctuations.
- This reciprocal regulation ensures appropriate plant growth and response to K nutrient status.
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