Impact of CCR1 silencing on the assembly of lignified secondary walls in Arabidopsis thaliana
Article first published online: 20 JUL 2009
© The Authors (2009). Journal compilation © New Phytologist (2009)
Volume 184, Issue 1, pages 99–113, October 2009
How to Cite
Ruel, K., Berrio-Sierra, J., Derikvand, M. M., Pollet, B., Thévenin, J., Lapierre, C., Jouanin, L. and Joseleau, J.-P. (2009), Impact of CCR1 silencing on the assembly of lignified secondary walls in Arabidopsis thaliana. New Phytologist, 184: 99–113. doi: 10.1111/j.1469-8137.2009.02951.x
- Issue published online: 2 SEP 2009
- Article first published online: 20 JUL 2009
- Received: 27 March 2009Accepted: 7 May 2009
- Arabidopsis thaliana;
- cell wall ultrastructure;
- cinnamoyl-CoA reductase;
- laser capture microdissection;
- quantitative immunogold labeling
- • A cinnamoyl-CoA reductase 1 knockout mutant in Arabidopsis thaliana was investigated for the consequences of lignin synthesis perturbation on the assembly of the cell walls.
- • The mutant displayed a dwarf phenotype and a strong collapse of its xylem vessels corresponding to lower lignin content and a loss of lignin units of the noncondensed type. Transmission electron microscopy revealed that the transformation considerably impaired the capacity of interfascicular fibers and vascular bundles to complete the assembly of cellulose microfibrils in the S2 layer, the S1 layer remaining unaltered. Such disorder in cellulose was correlated with X-ray diffraction showing altered organization.
- • Semi-quantitative immunolabeling of lignins showed that the patterns of distribution were differentially affected in interfascicular fibers and vascular bundles, pointing to the importance of noncondensed lignin structures for the assembly of a coherent secondary wall.
- • The use of laser capture microdissection combined with the microanalysis of lignins and polysaccharides allowed these polymers to be characterized into specific cell types. Wild-type A. thaliana displayed a two-fold higher syringyl to guaiacyl ratio in interfascicular fibers compared with vascular bundles, whereas this difference was less marked in the cinnamoyl-CoA reductase 1 knockout mutant.