Akademik Veri Yönetim Sistemi
Black Sea Journal of Agriculture, cilt.9, sa.1, ss.143-150, 2025 (TRDizin)
Flavonoids, a major class of secondary metabolites, play critical roles in plant development, environmental adaptation, and human health. Their biosynthesis is tightly regulated by intricate genetic networks involving transcription factors and non-coding RNAs, particularly microRNAs (miRNAs). Among them, miR858 and miR828 have emerged as key post-transcriptional regulators of flavonoid biosynthetic pathways by targeting MYB family transcription factors. This study comprehensively reviews the regulatory mechanisms of these two miRNA families in medicinal plants and Arabidopsis thaliana, with emphasis on their involvement in modulating gene expression linked to flavonoid accumulation. Recent findings highlight that miR858 not only represses flavonoidspecific MYBs but is also influenced by a regulatory peptide, miPEP858a, which enhances its own transcriptional activity, thereby altering phenylpropanoid metabolism and plant development. Similarly, miR828 functions both directly and via TAS4-derived siRNAs to downregulate anthocyanin-related MYBs, contributing to color modulation and stress responses. Functional analyses in model species and economically important plants demonstrate that the miR858–MYB and miR828–TAS4–MYB modules are evolutionarily conserved, yet display species-specific patterns in regulatory output. Moreover, tissue-specific expression studies, such as in Osmanthus fragrans, underline the spatial regulation of flavonoid-related genes by miR858a. The integration of omics data and experimental validation suggests that these miRNAs orchestrate transcriptional and epigenetic regulation, offering potential biotechnological targets to enhance flavonoid content. Overall, the study provides an in-depth synthesis of the current understanding of miR858 and miR828-mediated regulatory circuits, establishing their roles as central modulators in flavonoid biosynthesis across diverse plant taxa.