Resumen de Differential Gel Electrophoresis (DIGE) Identification of Bitter Pit Markers Expressed in Malus domestica
M. Krawitzky, I. Orera, R. Oria, J. Val
Bitter pit is a physiological disorder occurring in apple, pear, and quince and has been associated with calcium uptake or lack thereof. Studied for over a century, little is known regarding the development of bitter pit, what triggers its occurrence, and why there are no completely effective preventative treatments to reduce fruit loss. In the present study, Malus domestica proteins were collected from healthy and naturally occurring bitter pit fruit, cyanine dye labeled, and gel migrated in the second dimension. Gel spots were analyzed using SameSpots Software, picked, digested, and analyzed using an LC-LTQ-Orbitrap mass spectrometer. Approximately 250 protein spots were identified using SameSpots software. From these, a total of 42 spots varied significantly among healthy and bitter pit affected samples (p-value <0.05), when comparing average normalized spot volume. Twenty-four spots (8 proteins) were shared between bitter pit and healthy samples. Approximately 20 spots, identified as Actin, Mal d 1, Pathogenesis-related (PR), Thaumatin-like (TLP), and 1-aminocyclopropane-1-carboxylate oxidase were identified as being unique to either bitter pit or healthy samples. This study provides a first insight into proteins that may be considered markers for bitter pit development in apples.
