Proteomic Analysis of Perfect and Imperfect Flowers in Japanese Apricot (Prunus mume Sieb. et Zucc.)

Japanese apricot is a deciduous fruit and ornamental tree originating from Southeast China and has been widely cultivated in China. It has two types of flowers, perfect and imperfect. The imperfect flowers reduce yield of the tree. The objective of this study was to investigate the differentially expressed proteins between perfect and imperfect flowers. A combination of two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry approaches was used to detect and identify the differentially expressed proteins involved in pistil determination and development between perfect and imperfect flowers. The results showed that the protein maps from the perfect floral organs were similar to those from imperfect floral organs. Sixteen and 19 differentially expressed protein spots were detected in the young floral buds and in the open flower stages, respectively. Ten differentially expressed proteins from perfect and imperfect flowers at the bud and blossom stages were cut from the gel and identified by mass spectrometry. BLAST analysis demonstrated that these differential proteins were similar to other proteins in the databases providing biochemical evidence that the development of the pistil in Japanese apricot involved the physiological process of sugar metabolism, starch metabolism, photosynthesis and photorespiration.