Alterations of Phenylpropanoid Biosynthesis Lead to the Natural Formation of Pinkish-Skinned and White-Fleshed Strawberry ().

Anthocyanin content is important for both the external and internal fruit quality of cultivated strawberries, but the mechanism of its accumulation in pinkish-skinned and white-fleshed strawberries is puzzling. Here, we found that the factor determining variation in the flesh color was not the but the in the cultivated strawberry Benihoppe and its white-fleshed mutant Xiaobai. Compared with Benihoppe, there was no significant difference in the coding sequence and expression level of in Xiaobai's flesh. Instead, the transcription of was dramatically inhibited. The combined analyses of transcriptomics and metabolomics showed that the differential genes and metabolites were significantly enriched in the phenylpropanoid biosynthesis pathway. Furthermore, the transient overexpression of greatly restored anthocyanins' accumulation in Xiaobai's flesh and did not produce additional pigment species, as in Benihoppe. The transcriptional repression of was not directly caused by promoter methylations, lncRNAs, or microRNAs. In addition, the unexpressed , which resulted in the loss of cyanidin 3-O-glucoside in the flesh, was not due to methylation in promoters. Our findings suggested that the repression of was responsible for the natural formation of pinkish-skinned and white-fleshed strawberries.