Down-regulation of an Auxin Response Factor in the tomato induces modification of fine pectin structure and tissue architecture.

It has previously been shown that down-regulation of an auxin response factor gene (DR12) results in pleiotropic phenotypes including enhanced fruit firmness in antisense transgenic tomato (AS-DR12). To uncover the nature of the ripening-associated modifications affecting fruit texture, comparative analyses were performed of pectin composition and structure in cell wall pericarp tissue of wild-type and AS-DR12 fruit at mature green (MG) and red-ripe (RR) stages. Throughout ripening, pectin showed a decrease in methyl esterification and in the content of galactan side chains in both genotypes.

Investigation of ferulate deposition in endosperm cell walls of mature and developing wheat grains by using a polyclonal antibody.

A polyclonal antibody has been raised against ferulic acid ester linked to arabinoxylans (AX). 5-O-feruloyl-alpha-L-arabinofuranosyl(1-->4)-beta-D-xylopyranosyl was obtained by chemical synthesis, and was coupled to bovine serum albumin for the immunization of rabbit. The polyclonal antibody designated 5-O-Fer-Ara was highly specific for 5-O-(trans-feruloyl)-L-arabinose (5-O-Fer-Ara) structure that is a structural feature of cell wall AX of plants belonging to the family of Gramineae.

Characterization using Raman microspectroscopy of arabinoxylans in the walls of different cell types during the development of wheat endosperm.

The time course and pattern of arabinoxylan deposition in the wheat (Triticum aestivum) endosperm during grain development were studied using Raman spectroscopy. The presence of arabinoxylans (AX) is detected at the beginning of grain filling. At this stage, AX appear more substituted than at the later stages.

Deposition of cell wall polysaccharides in wheat endosperm during grain development: Fourier transform-infrared microspectroscopy study.

The time course and pattern deposition of the cell wall polysaccharides in the starchy endosperm of wheat (Triticum aestivum cv. Recital) during grain development was studied using Fourier transform infrared microspectroscopy (micro-FTIR). Three stages of grain development identified as key stages for cell wall construction were retained as follows: the end cellularization, the beginning of cell differentiation, and the beginning of maturation.

Arabinoxylan and (1-->3),(1-->4)-beta-glucan deposition in cell walls during wheat endosperm development.

Arabinoxylans (AX) and (1-->3),(1-->4)-beta-glucans are major components of wheat endosperm cell walls. Their chemical heterogeneity has been described but little is known about the sequence of their deposition in cell walls during endosperm development. The time course and pattern of deposition of the (1-->3) and (1-->3),(1-->4)-beta-glucans and AX in the endosperm cell walls of wheat (Triticum aestivum L.