title: Quantitative Proteomics-Based Reconstruction and Identification of Metabolic Pathways and Membrane Transport Proteins Related to Sugar Accumulation in Developing Fruits of Pear (Pyrus communis).
abstract: During their 6 month development, pear (Pyrus communis) fruits undergo drastic changes in their morphology and their chemical composition. To gain a better understanding of the metabolic pathways and transport processes active during fruit development, we performed a time-course analysis using mass spectrometry (MS)-based protein identification and quantification of fruit flesh tissues. After pre-fractionation of the samples, 2,841 proteins were identified. A principal component analysis (PCA) separated the samples from seven developmental stages into three distinct clusters representing the early, mid and late developmental phase. Over-representation analysis of proteins characteristic of each developmental phase revealed both expected and novel biological processes relevant at each phase. A high abundance of aquaporins was detected in samples from fruits in the cell expansion stage. We were able quantitatively to reconstruct basic metabolic pathways such as the tricarboxylic acid (TCA) cycle, which indicates sufficient coverage to reconstruct other metabolic pathways. Most of the enzymes that presumably contribute to sugar accumulation in pear fruits could be identified. Our data indicate that invertases do not play a major role in the sugar conversions in developing pear fruits. Rather, sucrose might be broken down by sucrose synthases. Further focusing on sugar transporters, we identified several putative sugar transporters from diverse families which showed developmental regulation. In conclusion, our data set comprehensively describes the proteome of developing pear fruits and provides novel insights about sugar accumulation as well as candidate genes for key reactions and transport steps.
authors.affiliation: Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Stefan
authors.initials: S
authors.lastname: Reuscher
authors.affiliation: College of Life Sciences, Ritsumeikan University, Kusatsu, 525-8577 Japan.
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Fukao
authors.affiliation: Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Reina
authors.initials: R
authors.lastname: Morimoto
authors.affiliation: Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601 Japan.
authors.forename: Shungo
authors.initials: S
authors.lastname: Otagaki
authors.affiliation: Faculty of Agriculture, Yamagata University, Tsuruoka, 997-8555 Japan RIKEN Center for Sustainable Resource Science, Yokohama, 230-0045 Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Oikawa
authors.affiliation: Yamagata Integrated Agricultural Research Center, Sagae, 999-7601 Japan.
authors.forename: Kanji
authors.initials: K
authors.lastname: Isuzugawa
authors.affiliation: Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, 464-8601 Japan shira@agr.nagoya-uni.ac.jp.
authors.forename: Katsuhiro
authors.initials: K
authors.lastname: Shiratake
mesh_terms: D020346:Aquaporins / Q000378:metabolism; D050260:Carbohydrate Metabolism; D005030:Ethylenes / Q000378:metabolism; D005638:Fruit / Q000254:growth & development* / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000378:metabolism*; D053858:Metabolic Networks and Pathways; D055432:Metabolomics; D058977:Molecular Sequence Annotation; D010940:Plant Proteins / Q000378:metabolism; D025341:Principal Component Analysis; D040901:Proteomics / Q000379:methods*; D031989:Pyrus / Q000254:growth & development* / Q000378:metabolism*; D011786:Quality Control
chemical_list: D020346:Aquaporins; D005030:Ethylenes; D026901:Membrane Transport Proteins; D010940:Plant Proteins; C036216:ethylene
keywords: Pear fruit; Proteomics; Pyrus communis; Sugar accumulation; Transport proteins