The potential role of R2R3-MYB gene family in the phenylpropanoid pathway and regulatory mechanism in Fragaria x ananassa

It is common knowledge that R2R3-MYB transcription factors play significant roles in plant biological and physiological processes, especially in the phenylpropanoid metabolism pathway. The cultivated strawberry (Fragaria x ananassa Duch.) is an octoploid (2n = 8x = 56) species from the Rosaceae family and it is also an important fruit crop species. However, the function of R2R3-MYB genes in strawberry remains largely unknown. Here, based on the genome of the cultivated strawberry cv. Reikou, 66 FanMYB genes were found and systematically analyzed. RNA-seq analysis revealed that some FanMYBs exhibited tissue-specific expressions and were methyl jasmonate (MeJA)-responsive. Phylogenetic relationships and protein-protein interaction analysis suggested that 13 FanMYBs were likely associated with phenylpropanoid metabolism. Out of these genes, FanMYB22, FanMYB36, FanMYB47, FanMYB49, and FanMYB63 were post-transcriptionally regulated by miR858 according to the degradome data analysis, suggesting the conservation and complex regulation network in F. x ananassa. Current findings provide a useful resource for future research on the function of FanMYBs and the regulatory mechanism of the phenylpropanoid pathway in strawberry.