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Title: TORC pathway intersects with a calcium sensor kinase network to regulate potassium sensing in Arabidopsis
Potassium (K) is an essential macronutrient for plant growth, and its availability in the soil varies widely, requiring plants to respond and adapt to the changing K nutrient status. We show here that plant growth rate is closely correlated with K status in the medium, and this K-dependent growth is mediated by the highly conserved nutrient sensor, target of rapamycin (TOR). Further study connected the TOR complex (TORC) pathway with a low-K response signaling network consisting of calcineurin B-like proteins (CBL) and CBL-interacting kinases (CIPK). Under high K conditions, TORC is rapidly activated and shut down the CBL–CIPK low-K response pathway through regulatory-associated protein of TOR (RAPTOR)–CIPK interaction. In contrast, low-K status activates CBL–CIPK modules that in turn inhibit TORC by phosphorylating RAPTOR, leading to dissociation and thus inactivation of the TORC. The reciprocal regulation of the TORC and CBL–CIPK modules orchestrates plant response and adaptation to K nutrient status in the environment.  more » « less
Award ID(s):
2041585
PAR ID:
10484124
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
PNAS
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
120
Issue:
47
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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