Transcriptome profiling of non-climacteric ‘Yellow’ melon during ripening: insights of sugar metabolism

Abstract

Background: The non-climacteric ‘Yellow’ melon (Cucumis melo, inodorus group) is an economically important crop and its quality is mainly determined by the sugar content. Thus, the knowledge of sugar metabolism and its related pathways can contribute to development of new field management and post-harvest practices, making it possible to deliver to consumers better quality fruits.Results: The RNA-seq associated with RT-qPCR analyses of four maturation stages were performed to identify important enzymes and pathways that are involved in the sugar metabolism profile in non-climacteric ‘Yellow’ melon fruit. We identified 895 genes 10 DAP-biased and 909 genes 40 DAP-biased. The global analyses evidenced pathways related to sucrose metabolism; hormone signal transduction; DNA and protein processing like significant metabolisms in the melon ripening. For fruit sucrose metabolism, 17 genes were differentially expressed (DE) whose pattern varied throughout fruit development.Conclusions: The results demonstrated important enzymes in the sugar pathway those are responsible for the sucrose content and maturation profile in non-climacteric ‘Yellow’ melon. New DE genes were first detected for melon in this study such as invertase inhibitor LIKE 3 (CmINH3), trehalose phosphate phosphatase (CmTPP1) and trehalose phosphate synthases (CmTPS5, CmTPS7, CmTPS9). Besides that, the results of the protein-protein network interaction demonstrated general characteristics of the transcriptome of young and full-ripe melon. Keywords: Cucumis melo, RNA-seq, sucrose, fruit ripening, gene expression