Apoplastic diffusion barriers in Arabidopsis.
During the development of Arabidopsis and other land plants, diffusion barriers are formed in the apoplast of specialized tissues within a variety of plant organs. While the cuticle of the epidermis is the primary diffusion barrier in the shoot, the Casparian strips and suberin lamellae of the endodermis and the periderm represent the diffusion barriers in the root. Different classes of molecules contribute to the formation of extracellular diffusion barriers in an organ- and tissue-specific manner. Cutin and wax are the major components of the cuticle, lignin forms the early Casparian strip, and suberin is deposited in the stage II endodermis and the periderm. The current status of our understanding of the relationships between the chemical structure, ultrastructure and physiological functions of plant diffusion barriers is discussed. Specific aspects of the synthesis of diffusion barrier components and protocols that can be used for the assessment of barrier function and important barrier properties are also presented.
University of Lausanne, Department of Plant Molecular Biology, Biophore Building, CH-1015 Lausanne, Switzerland.
Christiane
C
Nawrath
University of Bonn, Department of Ecophysiology of Plants, Institute of Cellular and Molecular Botany (IZMB), Kirschallee 1, D-53115 Bonn, Germany.
Lukas
L
Schreiber
University of Bonn, Department of Ecophysiology of Plants, Institute of Cellular and Molecular Botany (IZMB), Kirschallee 1, D-53115 Bonn, Germany.
Rochus Benni
RB
Franke
University of Lausanne, Department of Plant Molecular Biology, Biophore Building, CH-1015 Lausanne, Switzerland.
Niko
N
Geldner
Instituto de Hortofruticultura Subtropical y Mediterránea 'La Mayora' (IHSM-UMA-CSIC), Department of Plant Breeding, Estación Experimental 'La Mayora'. 29750 Algarrobo-Costa. Málaga. Spain.
José J
JJ
Reina-Pinto
University of British Columbia, Department of Botany, Vancouver, B.C. V6T 1Z4, Canada.
Ljerka
L
Kunst