miR156 As a central regulator of plant stress adaptation: Molecular networks, hormonal crosstalk, and breeding potential

• miR156 integrates SPL-dependent and SPL-independent pathways to coordinate plant responses to diverse abiotic and biotic stresses. • Crosstalk with hormone signaling (ABA, GA, JA, SLs) and interactions with other miRNAs reveal complex stress-resilience networks. • Multi-omics insights and CRISPR/Cas-mediated targeting of miR156 highlight its potential for precision breeding of stress-tolerant crops. MicroRNA156 (miR156) is an evolutionarily conserved regulator that plays a pivotal role in plant growth, development, and adaptation to environmental stress. In recent years, recent advances have elucidated how miR156 integrates into complex stress‐response networks through its canonical SQUAMOSA promoter-binding protein-like (SPL)‐dependent pathways and emerging SPL‐independent mechanisms. This review synthesizes current knowledge on miR156‐mediated responses to abiotic stresses, including drought, salinity, temperature extremes, and heavy metal toxicity, as well as its involvement in biotic stress defense. Particular attention is given to the molecular basis of its action, such as direct regulation of SPL transcription factors, modulation of other target genes, crosstalk with hormone signaling (ABA, GA, JA, and SLs), and synergistic interactions with other miRNAs. We also highlight recent advances in multi‐omics analyses and biotechnological applications, including CRISPR/Cas‐mediated editing of miR156 target sites for stress‐resilient crop breeding. Despite these advances, key challenges remain, notably the incomplete understanding of upstream regulators of miR156 and the scarcity of field‐based validation. Future research integrating single‐cell transcriptomics, spatial transcriptomics, and synthetic biology will help clarify the regulatory complexity of miR156. Bridging these mechanistic insights with crop improvement could establish miR156 manipulation as a key strategy for climate‐resilient agriculture.