Apoplastic polyesters in Arabidopsis surface tissues – A typical suberin and a particular cutin
The aliphatic monomer composition of isolated Arabidopsis leaf cuticles and of suberin from Arabidopsis was determined by gas chromatography and mass spectrometry. A biosynthetic pathway is discussed. Cutinized and suberized cell walls form physiological important plant–environment interfaces as the...
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Published in | Phytochemistry (Oxford) Vol. 66; no. 22; pp. 2643 - 2658 |
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Main Authors | , , , , , , |
Format | Journal Article |
Language | English |
Published |
Amsterdam
Elsevier Ltd
01.11.2005
Elsevier |
Subjects | |
Online Access | Get full text |
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Summary: | The aliphatic monomer composition of isolated
Arabidopsis leaf cuticles and of suberin from
Arabidopsis was determined by gas chromatography and mass spectrometry. A biosynthetic pathway is discussed.
Cutinized and suberized cell walls form physiological important plant–environment interfaces as they act as barriers limiting water and nutrient loss and protect from radiation and invasion by pathogens. Due to the lack of protocols for the isolation and analysis of cutin and suberin in
Arabidopsis, the model plant for molecular biology, mutants and transgenic plants with a defined altered cutin or suberin composition are unavailable, causing that structure and function of these apoplastic barriers are still poorly understood. Transmission electron microscopy (TEM) revealed that
Arabidopsis leaf cuticle thickness ranges from only 22
nm in leaf blades to 45
nm on petioles, causing the difficulty in cuticular membrane isolation. We report the use of polysaccharide hydrolases to isolate
Arabidopsis cuticular membranes, suitable for depolymerization and subsequent compositional analysis. Although cutin characteristic ω-hydroxy acids (7%) and mid-chain hydroxylated fatty acids (8%) were detected, the discovery of α,ω-diacids (40%) and 2-hydroxy acids (14%) as major depolymerization products reveals a so far novel monomer composition in
Arabidopsis cutin, but with chemical analogy to root suberin. Histochemical and TEM analysis revealed that suberin depositions were localized to the cell walls in the endodermis of primary roots and the periderm of mature roots of
Arabidopsis. Enzyme digested and solvent extracted root cell walls when subjected to suberin depolymerization conditions released ω-hydroxy acids (43%) and α,ω-diacids (24%) as major components together with carboxylic acids (9%), alcohols (6%) and 2-hydroxyacids (0.1%). This similarity to suberin of other species indicates that
Arabidopsis roots can serve as a model for suberized tissue in general. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0031-9422 1873-3700 |
DOI: | 10.1016/j.phytochem.2005.09.027 |