­Transcriptome profiling of non-climacteric ‘Yellow’ melon during ripening: insights on 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, knowledge of sugar metabolism and its related pathways can contribute to the development of new field management and post-harvest practices, making it possible to deliver better quality fruits to consumers. 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 ripening profile of non-climacteric ‘Yellow’ melon fruit focusing on sugar metabolism. We identified 895 genes 10 days after pollination (DAP)-biased and 909 genes 40 DAP-biased. The KEGG pathway enrichment analysis of these differentially expressed (DE) genes revealed that ‘hormone signal transduction’, ‘carbon metabolism’, ‘sucrose metabolism’, ‘protein processing in endoplasmic reticulum’ and ‘spliceosome’ were the most differentially regulated processes occurring during melon development. In the sucrose metabolism, five DE genes are up-regulated and twelve are down-regulated during fruit ripening. Conclusions: The results demonstrated important enzymes in the sugar pathway that 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 ). Furthermore, the results of the protein-protein network interaction demonstrated general characteristics of the transcriptome of young and full-ripe melon and provide new perspectives for the understanding of ripening.

KARAKTERISTIK KEMATANGAN BUAH MELON ‘PREMIER’ (Cucumis melo L.) BERDASARKAN SIFAT AKUSTIK

“…Pola perubahan nilai redness (a*) daging buah melon dapat dilihat pada Gambar 10. Nilai a* (redness) mengalami peningkatan seiring dengan peningkatan dari -2,44 ± 0,70 pada umur Hasil penelitian Schemberger et al (2020) pada buah melon non-klimakterik 'Yellow' dengan 4 umur panen melaporkan adanya tren serupa pada peningkatan nilai a* yang merepresentasikan perubahan warna dari hijau ke merah. Hal tersebut berkaitan dengan peningkatan karotenoid pada daging buah.…”