New Insights into the Physiology of Fruit Ripening of Apricot (prunus Armeniaca L.) and Japanese Plum (P. Salicina L.) Using Rna-Seq Analysis

The physiology of fruit ripening is a complex and is still an unknown process, that must be completely understood. To improve this knowledge, the postharvest behavior during the shelf-life period must be studied using modern omics tools. Thus, with this goal, postharvest monitoring of apricot and Japanese plum cultivars after different phytohormone treatments such as 1-MCP (ethylene-inhibitor) and Ethrel (ethylene-precursor) was carried out. Subsequently, a transcriptomic analysis of the most contrasting cultivars such as apricot ‘Goldrich’ and Japanese plum ‘Santa rosa’ was performed. After KEEG and protein-protein interaction network analysis, the most significant metabolic pathways involved in the ripening process were by far photosynthesis and plant hormone signal transduction. In addition, previous discover genes linked to fruit ripening such as pectinesterase or auxin-responsive protein, and proposing have been confirmed. According to FPKM difference between treatments, pectinesterase in the pentose and glucuronate interconversions was the most overexpressed in both species, being up-regulated by Ethrel. On the other side, auxin-responsive protein IAA and aquaporin PIP were both up-regulated by 1-MCP in ‘Goldrich’ and ‘Santa Rosa’ respectively. As for logFC criterion, chitinase and glutaredoxin 3 were up-regulated by Ethrel in ‘Goldrich’ and ‘Santa Rosa’ respectively, while photosystem I subunit V psaG (photosynthesis) was by 1-MCP in both species. Therefore, these findings provide an entire picture regarding the role of ethylene-related phytohormones during fruit ripening, confirming encoding genes linked to fruit ripening, and proposing new ones such as aquaporin PIP , chitinase , glutaredoxin 3, and psaG in apricot and, Japanese plum.