Researching The Mechanism Of Postharvest Senescence Of Non-climacteric Strawberry Fruit Using ITRAQ-based Analysis

For non-climacteric fruits, the respiratory increase is absent and no phytohormone is appearing to be critical for their ripening. They must remain on the parent plant to enable full ripening and be picked at or near the fully ripe stage to obtain the best eating quality. But huge losses often occur for their quick postharvest senescence. Here, to help understand the complex mechanism of postharvest non-climacteric fruits senescence, the proteins of strawberry fruit stored at 20℃ for 0,24 and 48 h were study by using iTRAQ-based quantitative proteomics approach, and 2472 proteins were quantified. The proteins of strawberry were comparied and the changes in metabolic pathways of postharvest senescence were explored.These efforts can provide a theoretical basis to explore the regulatory mechanism of strawberry postharvest senescence.The following are the main results of the experiment:1) After sequencing the proteins of strawberry fruit which stored for 0,24 and 48 h, a total of 3385 proteins were identified, among which,2472 proteins were quantified;2) By GO and KEGG Pathway annotation analysis, the identified proteins were found to be involved 12 kinds of molecular function,6 kinds cellular component and 12 kinds of biological process, and involved in 104 metabolic pathways;3) Compared to that in fruit stored for 0 h,17 and 20 proteins significantly up-and down-regulated in fruit stored for 24 h, respectively. And 70 and 63 proteins significantly up-and down-regulated in fruit stored for 48 h, respectively. In addition, compared to that in fruit stored for 24 h,71 and 45 proteins significantly up-and down-regulated in fruit stored for 48 h, respectively;4) For the differential expression proteins GO/Domain/KEGG Pathway enrichment analysis, the proteins between 24 h/0 h were found to be relatively fewer, which indicated that strawberry fruit still maintain normal metabolic after stored for 24 h. But for 48 h/24 h, the cellular components enrichment analysis showed that up-regulated protein were significantly enriched in "ribosome", "ribonucleoprotein complex" and "intracellular non-membrane-bounded organelle" function term, and down-regulated protein in molecular function were significantly enriched in the "photosynthesis", "photosynthetic membrane". Metabolic pathways involved energy metabolic, such as "photosynthesis" metabolism.