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 H 2 O 2  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 H 2 O 2  content in peach, which indicated that PpCOR 3 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.