2025/04/14 by Shan Jiang, Zhihui Sun, Zhenkai Feng +7 · 1 voice
Agricultural and Biological Sciences · #Plant Stress Responses and Tolerance #Plant nutrient uptake and metabolism #Plant Molecular Biology Research
paper · doi:10.1111/jipb.13906
openalex publication_date 2025/04/14 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
The calcineurin B-like protein (CBL)-CBL-interacting protein kinase (CIPK) Ca²⁺ sensors play crucial roles in the plant's response to drought stress. However, there have been few reports on the synergistic regulation of drought stress by CBL-CIPK and abscisic acid (ABA) core signaling components. In this study, we discovered that ZmCIPK33 positively regulates drought resistance in maize. ZmCIPK33 physically interacts with and is enhanced by phosphorylation from ZmSnRK2.10. Drought stress can activate ZmCIPK33, which is partially dependent on ZmSnRK2.10. ZmCIPK33 in combination with ZmSnRK2.10 can activate the slow anion channel ZmSLAC1 in Xenopus laevis oocytes independently of CBLs, whereas ZmCIPK33 or ZmSnRK2.10 alone is unable to do so. Furthermore, ZmCIPK33 phosphorylates ZmPP2C11 at Ser60, which leads to a reduction in the interaction between ZmPP2C11 and ZmEAR1 (the ortholog of Arabidopsis Enhancer of ABA co-Receptor 1) and weakens the phosphatase activity of ZmPP2C11, consequently, enhancing the activity of ZmSnRK2.10 in an in vitro assay and in the in-gel assay of the zmcipk33 mutant. Our findings provide novel insights into the molecular mechanisms underlying the reciprocal enhancement of Ca²⁺ and ABA signaling under drought stress in maize.