ZmSnRK2.10-mediated phosphorylation of ZmDNL1 attenuates ZmYAB15 activity to enhance drought resilience in maize.

Abstract

Drought stress represents a critical challenge to global agriculture, severely compromising plant growth and crop productivity through its disruption of intracellular signaling networks, with particular emphasis on protein kinase-mediated pathways and transcriptional regulation. In this study, we identified and characterized ZmDNL1 as a novel transcriptional regulator that serves as a negative modulator of drought tolerance in maize. Through comprehensive biochemical analyses, we demonstrated that ZmDNL1 physically interacts with ZmYAB15, a known negative regulator of drought tolerance, and potentiates its transcriptional regulatory activity. Most significantly, our investigation revealed that ZmSnRK2.10-mediated phosphorylation of three specific N-terminal residues in ZmDNL1 effectively attenuates ZmYAB15's transcriptional activity while maintaining the structural integrity of the ZmDNL1-ZmYAB15 protein complex, ultimately enhancing drought tolerance. These findings elucidate a previously unrecognized regulatory mechanism in which ZmSnRK2.10 orchestrates drought tolerance through phosphorylation-dependent fine tuning of the ZmDNL1-ZmYAB15 transcriptional regulatory module. Beyond advancing our fundamental understanding of drought response mechanisms in maize, this study provides valuable molecular targets for precision breeding strategies aimed at developing drought-resilient crop varieties.