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Abstract Soil salinity negatively affects crop yields worldwide. The dynamic transition between growth and salt stress responses helps plants cope with changing soil salinity status. However, the molecular mechanisms controlling such dynamic transitions remain poorly understood. Here, our study identified the target of rapamycin complex (TORC) as a central player in growth recovery from salt stress. We observed a rapid decline in TORC activity in Arabidopsis thaliana plants upon exposure to salt stress. Further investigation uncovered an intricate interplay between TORC and a salt response signaling network comprising calcineurin B-like (CBL) proteins and CBL-interacting kinases (CIPKs). Under standard growth conditions, Regulatory-Associated Protein of TOR (RAPTOR) promotes CBL–CIPK complex dissociation, thereby inhibiting CIPK. CIPK suppression is lifted under salt stress, and the activated CBL–CIPK complex phosphorylates RAPTOR, which in turn suppresses TORC activity. Thus, the reciprocal regulation of the TORC and CBL–CIPK modules orchestrates plant responses and adaptation to soil salinity. 

Current polymer network design suffers from intrinsic trade-offs, where polymer networks with high modulus often turn out to be in short of stretchability or fracture toughness. Here, we show a novel polymer network design through polymer-nanoparticle alternating hybrids that enable integrating the non-polymeric colloid deformation into polymer network design. The new class of polymer network exhibits colloidal yielding at small deformation before conformational change at higher elongation ratios, enabling simultaneous achievement of high Young’s modulus of E≈10-50 MPa, high yield strength of σ_Y~ 3-5 MPa, large stretchability of λ~7-10, and high fracture energy density of Γ~30 MJ/m^3. These results demonstrate a successful strategy to decouple the molecular mechanics for yield from that for stretchability or toughness, leading to new polymer networks design. 

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.