Transcriptome analysis of azacitidine (5-AzaC)-treatment affecting the development of early somatic embryogenesis in longan

DNA methylation plays key roles in regulating genes which control somatic embryogenesis (SE) in plant. 5-Azacytidine (5-AzaC) was considered as a common inhibitor of DNA methylation. Longan (Dimocarpus longan Lour.) SE has been established and used as model system for studying mechanism of SE in woody plants. However, effects of 5-AzaC on longan EC and the underlying mechanism at molecular level are rarely understood. In this study, RNA-seq was performed for transcriptome analysis of longan EC treated with or without 5-AzaC were analysed. A total of 29,232 expressed genes were obtained by aligned to longan reference genome and 1,617 differentially expressed genes (DEGs) were got in the pairwise comparisons of CK_vs_T. Integrating the KEGG enrichment pathway analysis showed that 'butanoate metabolism', 'C5-branched dibasic acid metabolism', 'sulphur metabolism', 'selenocompound metabolism', 'pantothenate and CoA biosynthesis', 'phagosome', and 'plant hormone signal transduction' were significantly enriched pathways, while the analysis of DEGs revealed that 5-AzaC-treatment could alter genes expression which related to the SE to adjust the complicated metabolic pathways. Therefore, these results indicated that 5-AzaC-treatment positively impact the development of early SE from longan and a decrease in the global DNA methylation level during early SE in longan.