Study on the differences of gene expression between pear and apple wild cultivation materials based on RNA-seq technique

Background: Pears and apples are both perennial deciduous trees of the Rosaceae family, and both are important economic fruit trees worldwide. The emergence of many varieties in the market has been mostly domesticated from wild to cultivated and regulated by the diferential expression of genes. However, the molecular process and pathways underlying this phenomenon remain unclear. Four typical wild and cultivar pear and apple trees at three developmental stages were used in our study to investigate the molecular process at the transcriptome level. Result: Physiological observations indicated the obvious diferences of size, weight, sugar acid content and peel color in wild and cultivar fruit among each developmental stage. Using next-generation sequencing based RNA-seq expression profling technology, we produced a transcriptome in procession of a large fraction of annotated pear and apple genes, and provided a molecular basis underlying the phenomenon of wild and cultivar fruit tree diferences. 5921 and 5744 diferential expression genes were identifed in pear and apple at three developmental stages respectively. We performed temporal and spatial diferential gene expression profling in developing fruits. Several key pathways such as signal transduction, photosynthesis, translation and many metabolisms were identifed as involved in the diferentiation of wild and cultivar fruits. Conclusion: In this study, we reported on the next-generation sequencing study of the temporal and spatial mRNA expression profling of pear and apple fruit trees. Also, we demonstrated that the integrated analysis of pear and apple transcriptome, which strongly revealed the consistent process of domestication in Rosaceae fruit trees. The results will be great infuence to the improvement of cultivar species and the utilization of wild resources.