Reference "Specific accumulation of polysaccharide-linked hydroxycinnamoyl esters in the cell walls of irregularly shaped and collapsed internode parenchyma cells of the dwarf rice mutant Fukei 71"

Reference ID

3164

Title

Specific accumulation of polysaccharide-linked hydroxycinnamoyl esters in the cell walls of irregularly shaped and collapsed internode parenchyma cells of the dwarf rice mutant Fukei 71

Source

Plant & cell physiology, 2000, vol. 41, pp. 776-784

Authors (6)

Nishikubo-N	Araki-T
Kajita-S	Kuroda-K
Kitano-H	Katayama-Y

Abstract

We examined a novel rice mutant, Fukei 71 (Oryza sativa L.), for alterations in
the levels of hydroxycinnamoyl esters that are linked to cell wall
polysaccharides and lignin units. In this mutant, a recessive mutation at a
single locus caused the collapse of parenchyma cells in the internodes. Light
microscopy revealed that the abnormal walls of internode parenchyma cells of
Fukei 71 were stained by the Maule reaction, which is specific for syringyl
units in phenolic compounds. These walls were not stained by Wiesner's reagent
(phloroglucinol-HCl), which reacts cinnamaldehyde in lignin. Levels of p-
coumaric acid (PCA) and ferulic acid (FA) were apparently elevated in the
abnormal tissue of the mutant. Western blotting analysis with antibodies
specific for phenylalanine ammonia-lyase (PAL) revealed higher levels of PAL in
the abnormal parenchyma tissue of Fukei 71 than in the parenchyma tissue of the
parent cultivar Fujiminori. These results and the observation that PAL was
produced at a greatly elevated level indicated that the phenylpropanoid pathway
that leads to the biosynthesis of polysaccharide-linked FA and PCA was
abnormally activated in the irregularly shaped and collapsed internode
parenchyma cells, in which the biosynthesis of lignin is normally repressed.