Understanding the global transcriptomic and metabolic changes during mulberry growth and development is essential for the enhancing fruit quality and optimizing breeding strategies. By integrating phenotypic, metabolomic, and transcriptomic data across 18 developmental and ripening stages of Da10 mulberry fruit, a global map of gene expression and metabolic changes was generated. Analysis revealed a gradual progression of morphological, metabolic, and transcriptional changes throughout the development and ripening phases. In this study, a new transcriptome transition, which was highly related to stress resistance, was observed after the full ripening stage. Moreover, a novel method was devised by integrating metabolome and phenotypic data to assess fruit quality and determine optimal harvest times early in the supply chain. Phase-specific co-expression networks involved in photosynthesis, quality regulation, and plant immunity were also constructed. Notably, eight flavonoids and six hub genes emerged as potential natural edible coatings or gene-editing targets for mulberry fruit to enhance resistance against biotic and abiotic stress. These findings should facilitate further research on stress resistance, post-harvest management, and sustainable agricultural development.
Fruit color, a defining characteristic in mulberry, varies markedly across cultivars, ranging from black and red to pink and white. However, the regulatory mechanisms governing pigmentation during fruit development remain poorly characterized. In this study, ATAC-seq and RNA-seq were integrated to investigate genome-wide chromatin accessibility and identify putative transcription factors involved in fruit development in Da10 (Yueshenda10, Morus atropurpurea Roxb.). Differentially accessible chromatin regions and differentially expressed genes were jointly analyzed to generate a genome-wide map of regulatory elements and transcriptional activity. This integrative approach enabled the reconstruction of a transcriptional regulatory network that facilitated the identification of candidate transcription factors and target genes associated with the biosynthesis of bioactive compounds, including sugars, flavonoids, diterpenoids, and anthocyanins. The expression levels of RNA-seq were confirmed by qRT-PCR. Motif enrichment analysis revealed seven and 23 enriched cis-elements at the S1 and S3 developmental stages, respectively. Integration with the transcriptional regulatory network established a robust framework for identifying candidate genes involved in the accumulation of key metabolites. Additionally, the dataset enables exploration of previously uncharacterized traits during turning stages of mulberry fruit development. Collectively, these findings advance our understanding of the regulatory architecture underlying fruit maturation and provide a foundation for future strategies to enhance mulberry fruit quality.