Journal of Plant Physiology

Department of Biotechnology, University of the Western Cape, Private Bag X17, Bellville 7535, South Africa.
Journal of plant physiology (Impact Factor: 2.56). 11/2011; 169(1):12-9. DOI: 10.1016/j.jplph.2011.10.001
Source: PubMed


Apple (Malus×domestica Borkh.) was used as a model to studying essential biological processes occurring in mature fruit hypanthium, commonly referred to as the fruit flesh or pulp, a highly active tissue where numerous metabolic processes such as carbohydrate metabolism and signal transduction occur. To understand the complex biological processes occurring in the hypanthium, a proteomics approach was used to analyze the proteome from freshly harvested ripe apple fruits. A total of 290 well-resolved spots were detected using two-dimensional gel electrophoresis (2-DE). Out of these, 216 proteins were identified representing 116 non-redundant proteins using matrix-assisted laser-desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and either the MASCOT or ProteinProspector engine for peptide mass fingerprinting (PMF) database searching. Identified proteins were classified into 13 major functional categories. Among these, the energy metabolism class was the most represented and included 50% of proteins homologous to Arabidopsis proteins that are involved in the response to biotic and abiotic stresses, suggesting a dual role for these proteins in addition to energy metabolism. We also identified dynein heavy chain in the hypanthium although this protein has been proposed as absent from angiosperms and thus suggest that the lack of dyneins in higher plants studied to date may not be a general characteristic to angiosperm genomic organisation. We therefore conclude that the detection and elucidation of the apple hypanthium proteome is an indispensable step towards the comprehension of fruit metabolism, the integration of genomic, proteomic and metabolomic data to agronomic trait information and thus fruit quality improvements.

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Available from: Ludivine Thomas, Mar 19, 2015
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    • "Some protein spots were assigned to more than one protein, possibly because the proteins co-migrated as a result of having the same pI and molecular weight. This pattern of co-migration is not uncommon in proteomic studies and was reported previously [23,24]. The 31 up- and 22 down-regulated X. a. pv. "
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