Publication
Title
Is acid-induced extension in seed plants only protein-mediated?
Author
Abstract
Cell wall extensibility controls the rate of plant cell growth. It is determined by intrinsic mechanical properties of wall polymers and by wall proteins modifying these polymers and their interactions. Heat-inactivation of endogenous cell wall proteins inhibited acid-induced extension of onion epidermis peels transverse to the net cellulose alignment in the cell wall but not parallel to it. In the former case the acid-induced extension could be controlled by expansins and in the latter case by pectins restricting shear between microfibrils. Heat-inactivated cell walls stretched transversely to the net cellulose orientation extended faster at pH 5.7 and slower at pH 4.5 compared to native walls. Expansins seem to be inactive at pH 5.7, so that faster extension may result from heat-induced viscous flow of pectins and conformational changes in the cuticle of the epidermis. This stimulation of wall extension is not seen at pH 4.5 as it is outweighed by the inhibitory effect of expansin heat-inactivation. Thus, cell wall extension in higher plants might be controlled by a complex interplay between protein-dependent and protein-independent mechanisms, the result of which depends on pH and preferential orientation of main wall polymers.
Language
English
Source (journal)
Plant signaling & behavior
Publication
2010
ISSN
1559-2316
Volume/pages
5:6(2010), p. 757-759
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Record
Identification
Creation 26.04.2010
Last edited 04.09.2013
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