Proteomic Analysis Of The Skin Of Rabbiteye Blueberry 'Bluegem'

The blueberry is a bush fruit belonging to the family Ericaceae, in the genus Vaccinium. This fruit has a variety of functional substances and has gained popularity recently due to its antioxidative property and various phytochemical contents including potential role in certain diseases like diabetes. Although a proteomic study has been conducted on a variety of fruits, research on the blueberry is still incomplete. In this study, the proteome of the skin of the rabbiteye blueberry, 'Bluegem', was analyzed using two-dimensional gel electrophoresis and then identified using a MALDI-TOF / TOF mass spectrometer. Approximately 810 protein spots were detected on 2DE maps among which 182 spots were thereafter identified using mass spectrometry. The functions of the identified proteins were classified according to the GO-MIPS funcat conversion table. As a result, 30% identified protein spots were functionally classified into metabolism-related proteins (glutamine synthetase, chalcone synthase, anthocyanidin synthase, and flavanone 3-hydroxylase) and 30% to energy-related proteins (enolase, malate dehydrogenase, and ATP synthase). Other proteins were associated with protein fate, cell rescue, defense response, and virulence, such as the heat shock protein peptidyl prolyl isomerase. There were 74 unknown or unclassified proteins included in the gel-electrophoresis separation, which accounted for 40% in functional classification. Further study of the proteins that are currently annotated as "unidentified" or "unknown" will provide more information of the specific functions of the proteins expressed in blueberries.