Calcium Signaling as an Emerging Integrator of Manganese Homeostasis in Arabidopsis: From Molecular Mechanisms to Adaptive Strategies.
- 2026-05-02
- Plants (Basel, Switzerland) 15(9)
- Xiaoyun Zhang
- Baochen Zhang
- Ye Wang
- Lijuan Zeng
- Zhixuan Wen
- Ming Lei
- Li Li
- PubMed: 42122888
- DOI: 10.3390/plants15091396
Study Design
- Type
- Review
Manganese (Mn) is essential for plants, but its fluctuating soil availability-deficiency in alkaline soils and toxicity in acidic soils-challenges crop productivity. Breakthroughs in Arabidopsis have uncovered Ca2+ signaling as a key integrator of Mn status. This review synthesizes these discoveries into an emerging Arabidopsis-centered framework. Under Mn deficiency, sustained Ca2+ oscillations activate CPK21/23, which phosphorylate the importer NRAMP1 at Thr498 to enhance Mn uptake. Under Mn excess, a rapid Ca2+ transient triggers a multi-layered cascade: CPK4/5/6/11 activates MTP8 (Ser31/32) for vacuolar sequestration, while CBL2/3-CIPK3/9/26 sequentially suppresses MTP8 (Ser35, peak 24 h) and MTP11 (Ser194/201, peak 36 h)-a multi-tiered "brake" system. Concurrently, CBL1/9-CIPK23 induces NRAMP1 endocytosis (Ser20/22) to limit Mn uptake. The IRT1 transporter directly binds cytoplasmic Mn2+ and triggers its own degradation via CIPK23, thereby converging with Ca2+ signaling. The BRI1-CNGC12 module generates Mn-induced Ca2+ signals. By organizing current knowledge into a hierarchical framework, this review provides a working model for future research and outlines translational opportunities for engineering Mn-resilient crops.