Identification of COR413 Gene Family in Peach and Its Expression in Low Temperature and LTC Treatment at Postharvest

Abstract

Peach were susceptible to chilling injury during low temperature (0 o C) storage at postharvest, and LTC (Low temperature conditioning) treatment could reduce chilling injury such as of H2O2 production and fruit browning. In order to study the function of peach COR413 in the regulation of postharvest chilling injury in peach 'Beijing No. 9', four COR413 gene family members were identified based on the peach genome database, namely PpCOR1~PpCOR4. Phylogenetic analysis showed that the four PpCORs could be clustered into two subfamilies. PpCOR1~PpCOR3 belonged to the first subfamily, and most of the members in this subfamily were located in plasma membrane. PpCOR4 belongs to the second subfamily, and its members are mainly located in thylakoid membrane. The cis-acting elements analysis of PpCORs promoter showed that PpCOR3 contained abundant abiotic stress responsive and hormone responsive elements such as jasmonate and abscisic acid. The results of gene expression showed that PpCOR3 was induced by low temperature while LTC treatment could repress the induction of PpCOR3 by low temperature. Interestingly, the expression of PpCOR3 was positively correlated with the change of H2O2 content in peach, which indicated that PpCOR3 was involved in the regulation of postharvest chilling injury in peach fruit. This result provides a theoretical basis for the study of postharvest storage and quality maintenance of peach fruit as well as the breeding of cold resistant peach varieties.