ABA-mediated miR5290 promotes anthocyanin biosynthesis by inhibiting the expression of FaMADS1 in postharvest strawberry fruit

Abscisic acid (ABA) as a pivotal phytohormone is found to play a positive role in the ripening of strawberry fruit (Fragaria × ananassa Duch.) via regulating miR5290 and MADS-box transcription factor (TF) FaMADS1. In this work, the functional cross-link between miR5290 and FaMADS1 in response to ABA in strawberry fruit was investigated. Results showed that miR5290 displayed a fruit-specific expression pattern and its expression level increased during the accumulation of anthocyanin. ABA accelerated anthocyanin biosynthesis by enhancing anthocyanin biosynthesis-related enzyme activities. Meanwhile, ABA treatment promoted the expression level of miR5290 while repressing FaMADS1 expression. In addition, silencing of miR5290 in wild-type strawberry fruit and dual-luciferase reporter in N. benthamiana leaves also demonstrated the negative regulation of miR5290 on FaMADS1 expression. These results elucidated the possible mechanism of the coordination regulation of miR5290 and FaMADS1 in ABA-mediated ripening of strawberry fruit.