Multifaceted Regulation and Functional Versatility of miR164 in Plant: From Molecular Mechanisms to Crop Improvement

MicroRNA164 (miR164), a highly conserved plant-specific miRNA family, serves as a pivotal regulator in diverse aspects of plant growth, development, and stress responses primarily through targeting NAC transcription factors and other downstream genes. This comprehensive review systematically presents the structural characteristics, regulatory mechanisms, and functional diversity of miR164 across various plant species. The evolutionary conservation in mature sequences of miR164 determines functional specificity, with base variations at non-cleavage sites potentially expanding the target repertoire and regulatory scenarios; the species-specific expansion of miR164 members exhibits partial functional redundancy and enables functional diversification. The conserved miR164-NAC regulatory module and newly identified non-NAC targets have been revealed to be involved in plant growth and response to stresses. The precise spatiotemporal expression patterns of miR164, dynamically regulated by specific transcriptional controllers and environmental cues, attract further study. Given its multifunctional roles, miR164 and miR164-TF modules represent a promising target for crop genetic improvement. This review introduces the current research status on miR164 regulatory networks, functional versatility, and validation methodologies, while highlighting its significant potential in developing stress-resilient crops and enhancing agricultural productivity through targeted genetic engineering approaches.