Abstract: Flower-bud formation specific protein of mature spur from apple trees (Malus domestica Borkh.) was studied by employing two-dimensional electrophoresis (2-DE), bioinformatics , and mass spectrometry (MS). The result showed that there were 283 differential protein spots existed and changed in quality and quantity on two 2-DE maps for ‘ Fuji’ at seventh week, of which 162 spots increased and 110 spots decreased in quantity. Four protein spots(16.4、30.2、40.3、65.1kD)were observed the flower bud initial stage 1(inflorescence appears)in two-dimensiononal electrophoresis maps; Three protein spots(39.3、60.2、66.3kD)were observed the initial stage 2(Lateral bud appears) in two-dimensiononal electrophoresis maps; one protein spot(77.1kD)was observed the sepal in two-dimensiononal electrophoresis maps.Four special proteins were observed by peptide mass fingerprinting and matrix-assisted laser desorption ionization time of flight mass spectrometry. By the analysis of four special proteins spots with peptide mass fingerprinting and matrix-assisted laser desorption ionization time of flight mass spectrometry. When Red Fuji apple begin to spur flower buds. At the same time identified proteins and their putative functions were presented through the retrieval different database. One of them, spot No.256(16.4kD)、298（30.2 kD）were unknown proteins and spot No.327(40.3kD)was identified as the synthesis enzyme protein. Spot No.367(40.3kD)was identified as a RNA-binding protein involved in transcription. Technical details concerning database queries and successful protein identification rate in the absence of a sequenced genome are reported and discussed.

Key words: Apple tree, Flower bud, Proteomics, Specific protein, Two-dimensional electrophoresis, Peptide mass fingerprinting