title: Proteomic analysis of papaya fruit ripening using 2DE-DIGE.
abstract: Papayas have a very short green life as a result of their rapid pulp softening as well as their susceptibility to physical injury and mold growth. The ripening-related changes take place very quickly, and there is a continued interest in the reduction of postharvest losses. Proteins have a central role in biological processes, and differential proteomics enables the discrimination of proteins affected during papaya ripening. A comparative analysis of the proteomes of climacteric and pre-climacteric papayas was performed using 2DE-DIGE. Third seven proteins corresponding to spots with significant differences in abundance during ripening were submitted to MS analysis, and 27 proteins were identified and classified into six main categories related to the metabolic changes occurring during ripening. Proteins from the cell wall (alpha-galactosidase and invertase), ethylene biosynthesis (methionine synthase), climacteric respiratory burst, stress response, synthesis of carotenoid precursors (hydroxymethylbutenyl 4-diphosphate synthase, GcpE), and chromoplast differentiation (fibrillin) were identified. There was some correspondence between the identified proteins and the data from previous transcript profiling of papaya fruit, but new, accumulated proteins were identified, which reinforces the importance of differential proteomics as a tool to investigate ripening and provides potentially useful information for maintaining fruit quality and minimizing postharvest losses.
authors: Laboratório de Química, Bioquímica e Biologia Molecular de Alimentos, FCF, Universidade de São Paulo, SP, Brazil.
authors: Silvia Beserra
authors: SB
authors: Nogueira
authors: Carlos Alberto
authors: CA
authors: Labate
authors: Fabio Cesar
authors: FC
authors: Gozzo
authors: Eduardo Jorge
authors: EJ
authors: Pilau
authors: Franco Maria
authors: FM
authors: Lajolo
authors: João Roberto
authors: JR
authors: Oliveira do Nascimento
mesh_terms: D029441:Carica / Q000378:metabolism*; D002473:Cell Wall / Q000378:metabolism; D002853:Chromatography, Liquid / Q000379:methods; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods*; D005030:Ethylenes / Q000737:chemistry; D005638:Fruit / Q000378:metabolism*; D020869:Gene Expression Profiling / Q000379:methods; D018506:Gene Expression Regulation, Plant; D007091:Image Processing, Computer-Assisted; D013058:Mass Spectrometry / Q000379:methods; D018087:Plastids / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D013997:Time Factors
chemical_list: D005030:Ethylenes; C036216:ethylene