Plant fluid proteomics: Delving into the xylem sap, phloem sap and apoplastic fluid proteomes

Jorge Rodríguez-Celma, Laura Ceballos-Laita, Michael A. Grusak, Javier Abadía, Ana-Flor López-Millán

Research output: Contribution to journalArticle

36 Citations (Scopus)

Abstract

The phloem sap, xylem sap and apoplastic fluid play key roles in long and short distance transport of signals and nutrients, and act as a barrier against local and systemic pathogen infection. Among other components, these plant fluids contain proteins which are likely to be important players in their functionalities. However, detailed information about their proteomes is only starting to arise due to the difficulties inherent to the collection methods. This review compiles the proteomic information available to date in these three plant fluids, and compares the proteomes obtained in different plant species in order to shed light into conserved functions in each plant fluid. Inter-species comparisons indicate that all these fluids contain the protein machinery for self-maintenance and defense, including proteins related to cell wall metabolism, pathogen defense, proteolysis, and redox response. These analyses also revealed that proteins may play more relevant roles in signaling in the phloem sap and apoplastic fluid than in the xylem sap. A comparison of the proteomes of the three fluids indicates that although functional categories are somewhat similar, proteins involved are likely to be fluid-specific, except for a small group of proteins present in the three fluids, which may have a universal role, especially in cell wall maintenance and defense.
Original languageEnglish
Pages (from-to)991–1002
JournalBiochimica et Biophysica Acta - Proteins and Proteomics
Volume1864
Issue number8
Early online date28 Mar 2016
DOIs
Publication statusPublished - Aug 2016

Keywords

  • Apoplastic fluid
  • Phloem sap
  • Proteome
  • Xylem sap

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