Suppression of CCR impacts metabolite profile and cell wall composition in Pinus radiata tracheary elements.
Plant Mol Biol
; 81(1-2): 105-17, 2013 Jan.
Article
en En
| MEDLINE
| ID: mdl-23131896
ABSTRACT
Suppression of the lignin-related gene cinnamoyl-CoA reductase (CCR) in the Pinus radiata tracheary element (TE) system impacted both the metabolite profile and the cell wall matrix in CCR-RNAi lines. UPLC-MS/MS-based metabolite profiling identified elevated levels of p-coumaroyl hexose, caffeic acid hexoside and ferulic acid hexoside in CCR-RNAi lines, indicating a redirection of metabolite flow within phenylpropanoid metabolism. Dilignols derived from coniferyl alcohol such as G(8-5)G, G(8-O-4)G and isodihydrodehydrodiconiferyl alcohol (IDDDC) were substantially depleted, providing evidence for CCR's involvement in coniferyl alcohol biosynthesis. Severe CCR suppression almost halved lignin content in TEs based on a depletion of both H-type and G-type lignin, providing evidence for CCR's involvement in the biosynthesis of both lignin types. 2D-NMR studies revealed minor changes in the HG-ratio and consequently a largely unchanged interunit linkage distribution in the lignin polymer. However, unusual cell wall components including ferulate and unsaturated fatty acids were identified in TEs by thioacidolysis, pyrolysis-GC/MS and/or 2D-NMR in CCR-RNAi lines, providing new insights into the consequences of CCR suppression in pine. Interestingly, CCR suppression substantially promoted pyrolytic breakdown of cell wall polysaccharides, a phenotype most likely caused by the incorporation of acidic compounds into the cell wall matrix in CCR-RNAi lines.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas de Plantas
/
Pinus
/
Aldehído Oxidorreductasas
Idioma:
En
Revista:
Plant Mol Biol
Asunto de la revista:
BIOLOGIA MOLECULAR
/
BOTANICA
Año:
2013
Tipo del documento:
Article
País de afiliación:
Nueva Zelanda