Abstract
Transgenic tobacco (Nicotiana tabacum L.) plants in which the activity of 4-coumarate:coenzyme A ligase is very low contain a novel lignin in their xylem. Details of changes in hydroxycinnamic acids bound to cell walls and in the structure of the novel lignin were identified by base hydrolysis, alkaline nitrobenzene oxidation, pyrolysis-gas chromatography, and 13C-nuclear magnetic resonance analysis. In the brownish tissue of the transgenic plants, the levels of three hydroxycinnamic acids, p-coumaric, ferulic, and sinapic, which were bound to cell walls, were apparently increased as a result of down-regulation of the expression of the gene for 4-coumarate:coenzyme A ligase. Some of these hydroxycinnamic acids were linked to cell walls via ester and ether linkages. The accumulation of hydroxycinnamic acids also induced an increase in the level of condensed units in the novel lignin of the brownish tissue. Our data indicate that the behavior of some of the incorporated hydroxycinnamic acids resembles lignin monomers in the brownish tissue, and their accumulation results in dramatic changes in the biosynthesis of lignin in transgenic plants.
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- Dwivedi U. N., Campbell W. H., Yu J., Datla R. S., Bugos R. C., Chiang V. L., Podila G. K. Modification of lignin biosynthesis in transgenic Nicotiana through expression of an antisense O-methyltransferase gene from Populus. Plant Mol Biol. 1994 Oct;26(1):61–71. doi: 10.1007/BF00039520. [DOI] [PubMed] [Google Scholar]
- Elkind Y., Edwards R., Mavandad M., Hedrick S. A., Ribak O., Dixon R. A., Lamb C. J. Abnormal plant development and down-regulation of phenylpropanoid biosynthesis in transgenic tobacco containing a heterologous phenylalanine ammonia-lyase gene. Proc Natl Acad Sci U S A. 1990 Nov;87(22):9057–9061. doi: 10.1073/pnas.87.22.9057. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Iiyama K., Lam TBT., Stone B. A. Covalent Cross-Links in the Cell Wall. Plant Physiol. 1994 Feb;104(2):315–320. doi: 10.1104/pp.104.2.315. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ishii T. Isolation and characterization of a diferuloyl arabinoxylan hexasaccharide from bamboo shoot cell-walls. Carbohydr Res. 1991 Oct 14;219:15–22. doi: 10.1016/0008-6215(91)89039-i. [DOI] [PubMed] [Google Scholar]
- Kajita S., Katayama Y., Omori S. Alterations in the biosynthesis of lignin in transgenic plants with chimeric genes for 4-coumarate: coenzyme A ligase. Plant Cell Physiol. 1996 Oct;37(7):957–965. doi: 10.1093/oxfordjournals.pcp.a029045. [DOI] [PubMed] [Google Scholar]
- Khan M. R., Ceriotti A., Tabe L., Aryan A., McNabb W., Moore A., Craig S., Spencer D., Higgins T. J. Accumulation of a sulphur-rich seed albumin from sunflower in the leaves of transgenic subterranean clover (Trifolium subterraneum L.). Transgenic Res. 1996 May;5(3):179–185. doi: 10.1007/BF01969707. [DOI] [PubMed] [Google Scholar]
- Lee D., Douglas C. J. Two divergent members of a tobacco 4-coumarate:coenzyme A ligase (4CL) gene family. cDNA structure, gene inheritance and expression, and properties of recombinant proteins. Plant Physiol. 1996 Sep;112(1):193–205. doi: 10.1104/pp.112.1.193. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lewis N. G., Yamamoto E. Lignin: occurrence, biogenesis and biodegradation. Annu Rev Plant Physiol Plant Mol Biol. 1990;41:455–496. doi: 10.1146/annurev.pp.41.060190.002323. [DOI] [PubMed] [Google Scholar]
- Ye Z. H., Kneusel R. E., Matern U., Varner J. E. An alternative methylation pathway in lignin biosynthesis in Zinnia. Plant Cell. 1994 Oct;6(10):1427–1439. doi: 10.1105/tpc.6.10.1427. [DOI] [PMC free article] [PubMed] [Google Scholar]