JXB Advance Access originally published online on November 1, 2005
Journal of Experimental Botany 2005 56(422):3171-3182; doi:10.1093/jxb/eri314
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Published by Oxford University Press [2005] on behalf of the Society for Experimental Biology.
RESEARCH PAPER |
Biochemical and immunohistochemical analysis of pectic polysaccharides in the cell walls of Arabidopsis mutant QUASIMODO 1 suspension-cultured cells: implications for cell adhesion
1INRA-Biopolymères, Interactions, Assemblages, BP 71627, F-44316 Nantes Cedex 3, France
2Université de Nantes, Groupe de Physiologie et Pathologie Végétales, Faculté des Sciences et Techniques, 2 rue de la Houssinière, BP 92208, F-44322, Nantes Cedex 3, France
* To whom correspondence should be addressed. E-mail: lahaye{at}nantes.inra.fr
Mutation in the Arabidopsis thaliana QUASIMODO 1 gene (QUA1), which encodes a putative glycosyltransferase, reduces cell wall pectin content and cell adhesion. Suspension-cultured calli were generated from roots of wild-type (wt) and qua1-1 A. thaliana plants. The altered cell adhesion phenotype of the qua1-1 plant was also found with its suspension-cultured calli. Cell walls of both wt and qua1-1 calli were analysed by chemical, enzymatic and immunohistochemical techniques in order to assess the role of pectic polysaccharides in the mutant phenotype. Compared with the wt, qua1-1 calli cell walls contained more arabinose (23.6 versus 21.6 mol%), rhamnose (3.1 versus 2.7 mol%), and fucose (1.4 versus 1.2 mol%) and less uronic acid (24.2 versus 27.6 mol%), and they were less methyl-esterified (DM: 22.9% versus 30.3%). When sequential pectin extraction of calli cell walls was performed, qua1-1 water-soluble and chelator-soluble extracts contained more arabinose and less uronic acid than wt. Water-soluble pectins were less methyl-esterified in qua1-1 than in wt. Chelator-soluble pectins were more acetyl-esterified in qua1-1. Differences in the cell wall chemistry of wt and mutant calli were supported by a reduction in JIM7 labelling (methyl-esterified homogalacturonan) of the whole wall in small cells and particularly by a reduced labelling with 2F4 (calcium-associated homogalacturonan) in the middle lamella at tricellular junctions of large qua1-1 cells. Differences in the oligosaccharide profile obtained after endopolygalacturonase degradation of alkali extracts from qua1-1 and wt calli indicated variations in the structure of covalently bonded homogalacturonan. About 29% more extracellular polymers rich in pectins were recovered from the calli culture medium of qua1-1 compared with wt. These results show that perturbation of QUASIMODO 1-1 gene expression in calli resulted in alterations of homogalacturonan content and cell wall location. The consequences of these structural variations are discussed with regard to plant cell adhesion.
Key words: Arabidopsis thaliana, cell adhesion, cell culture, cell wall, pectin
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  F. Guillon, S. Philippe, B. Bouchet, M.-F. Devaux, P. Frasse, B. Jones, M. Bouzayen, and M. Lahaye Down-regulation of an Auxin Response Factor in the tomato induces modification of fine pectin structure and tissue architecture J. Exp. Bot., February 10, 2008; (2008) erm323v1. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Siedlecka, S. Wiklund, M.-A. Peronne, F. Micheli, J. Lesniewska, I. Sethson, U. Edlund, L. Richard, B. Sundberg, and E. J. Mellerowicz Pectin Methyl Esterase Inhibits Intrusive and Symplastic Cell Growth in Developing Wood Cells of Populus Plant Physiology, February 1, 2008; 146(2): 554 - 565. [Abstract] [Full Text] [PDF]
|
|