Abstract
Effects of indole-3-acetic acid (IAA) on the mechanical properties of cell walls and structures of cell wall polysaccharides in outer and inner tissues of segments of dark grown squash (Cucurbita maxima Duch.) hypocotyls were investigated. IAA induced the elongation of unpeeled, intact segments, but had no effect on the elongation of peeled segments. IAA induced the cell wall loosening in outer tissues as studied by the stress-relaxation analysis but not in inner tissues. IAA-induced changes in the net sugar content of cell wall fractions in outer and inner tissues were very small. Extracted hemicellulosic xyloglucans derived from outer tissues had a molecular weight about two times as large as in inner tissues, and the molecular weight of xyloglucans in both outer and inner tissues decreased during incubation. IAA substantially accelerated the depolymerization of xyloglucans in outer tissues, while it prevented that in inner tissues. These results suggest that IAA-induced growth in intact segments is due to the cell wall loosening in outer tissues, and that IAA-accelerated depolymerization of hemicellulosic xyloglucans in outer tissues is involved in the cell wall loosening processes.
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Selected References
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- Fujihara S., Yamamoto R., Masuda Y. Viscoelastic properties of plant cell walls--I. Mathematical formulation for stress relaxation with consideration for pre-extension rate. Biorheology. 1978;15(2):63–75. doi: 10.3233/bir-1978-15201. [DOI] [PubMed] [Google Scholar]
- Galambos J. T. The reaction of carbazole with carbohydrates. I. Effect of borate and sulfamate on the carbazole color of sugars. Anal Biochem. 1967 Apr;19(1):119–132. doi: 10.1016/0003-2697(67)90141-8. [DOI] [PubMed] [Google Scholar]
- Kutschera U., Briggs W. R. Rapid auxin-induced stimulation of cell wall synthesis in pea internodes. Proc Natl Acad Sci U S A. 1987 May;84(9):2747–2751. doi: 10.1073/pnas.84.9.2747. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Labavitch J. M., Ray P. M. Turnover of cell wall polysaccharides in elongating pea stem segments. Plant Physiol. 1974 May;53(5):669–673. doi: 10.1104/pp.53.5.669. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Terry M. E., Jones R. L. Soluble Cell Wall Polysaccharides Released from Pea Stems by Centrifugation : I. EFFECT OF AUXIN. Plant Physiol. 1981 Sep;68(3):531–537. doi: 10.1104/pp.68.3.531. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wakabayashi K., Sakurai N., Kuraishi S. Sugar Composition and Molecular Weight Distribution of Cell Wall Polysaccharides in Outer and Inner Tissues from Segments of Dark Grown Squash (Cucurbita maxima Duch.) Hypocotyls. Plant Physiol. 1990 Jul;93(3):998–1004. doi: 10.1104/pp.93.3.998. [DOI] [PMC free article] [PubMed] [Google Scholar]