Combined analysis of lncRNAs and mRNAs associated with coloration and wax formation during 'Fumei' Apple development

'Fumei' apple is characterized by high anthocyanin content and thick wax layer. Long non-coding RNAs (lncRNAs) play essential roles in the growth and development of various plants via regulation of gene expression. This study explored the potential mechanism underlying anthocyanin accumulation and cuticular wax formation during the development of 'Fumei' apple fruit. The results demonstrated that anthocyanin accumulation correlates with fruit coloration, while wax content drives wax layer formation. A total of 6039 and 3410 differentially expressed genes (DEGs), as well as 230 and 131 differentially expressed lncRNAs (DELs) were identified in the M1/M2 and M2/M3 pairs, respectively, by using RNA-seq. In the M1/M2 pair, the DEGs were mainly enriched in the 'photosynthesis' and 'flavonoid biosynthesis' pathways; in the M2/M3 pair, the DEGs were significantly enriched in the 'photosynthesis' and 'cutin, suberine and wax biosynthesis' pathways. Furthermore, the structural and regulatory genes involved in anthocyanin and cuticular wax biosynthesis were investigated, and the potential lncRNAs and genes that may control the anthocyanin and cuticular wax biosynthesis were identified. This study provides candidate lncRNAs and potential regulatory genes associated with both the regulation of anthocyanins and wax during apple development.