Transcriptional dynamics of early developing tomato (Solanum lycopersicum l.) fruit based on RNA-seq analysis

Tomato (Solanum lycopersicum L.) is one of the most popular vegetable species grown worldwide. Functional genomic analysis of genes in the early flower and fruit stages are the key factors for genetic enhancement of tomato fruits for increased yield and quality. In the current study, RNA-Seq datasets were generated for the Chico cultivar at six growth stages, 0, 3, 5, 7, 9 and 12 days after pollination (DAP). The computational analysis of transcriptomes and heat map showed close relationships among transcripts regulated at 3 and 5 DAP and at 7 and 9 DAP, whereas transcripts regulated at 12 DAP were more distant. Annotated transcripts and KEGG analysis showed that starch and sucrose pathway experienced the most dynamic changes resulting in the synthesis of several soluble sugars, e.g., sucrose, β-D-fructose, α-D-glucose, trehalose, maltose and 1,4-β-D-xylan. Enzymes activated in this pathway included levansucrase, phosphotransferse, invertase, pectin methyl esterase (PME), glucan synthase and cellulase. In general, the results provided improved insights into the mechanisms underlying early fruit development in tomatoes.