Proteomic analysis of postharvest peach fruit subjected to chilling stress or non-chilling stress temperatures during storage

- Proteins related to membrane stability was reduced under chilling stress.
- sHSPs and antioxidant defense system were higher expressed at 5 °C.
- Enhancing expressions of expansin and pectate lyase led to softening at10 °C.
- PR proteins related with decay development was increased under non-chilling stress.

Proteome patterns from peach fruit subjected to chilling stress (5 °C) and non-chilling stress (10 °C) temperatures were compared by 2-dimensional gel electrophoresis (2-DE) and MALDI-TOF/TOF mass spectrometry. Among the 60 differentially expressed proteins detected by 2-DE, those involved in stress response and defense were the most abundant. Proteins associated with membrane stability, as well as sucrose content were reduced in fruit stored at 5 °C, possibly contributing to the development of chilling injury (CI) seen at 5 °C. In addition, small heat shock proteins and components of the antioxidant defense system were expressed at higher levels under chilling stress. In contrast, storage at non-chilling temperature (10 °C) promoted the softening of peach fruit accompanied by increased levels of expansin and pectate lyase. The expression of pathogenesis-related proteins also increased at 10 °C, in parallel with the relatively higher incidence of decay observed at this temperature.