Strong decrease in lignin content without significant alteration of plant development is induced by simultaneous down-regulation of cinnamoyl CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD) in tobacco plants

Citation
M. Chabannes et al., Strong decrease in lignin content without significant alteration of plant development is induced by simultaneous down-regulation of cinnamoyl CoA reductase (CCR) and cinnamyl alcohol dehydrogenase (CAD) in tobacco plants, PLANT J, 28(3), 2001, pp. 257-270
Citations number
48
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Plant Sciences","Animal & Plant Sciences
Journal title
PLANT JOURNAL
ISSN journal
0960-7412 → ACNP
Volume
28
Issue
3
Year of publication
2001
Pages
257 - 270
Database
ISI
SICI code
0960-7412(200111)28:3<257:SDILCW>2.0.ZU;2-T
Abstract
Different transgenic tobacco lines down-regulated for either one or two enz ymes of the monolignol pathway were compared for their lignin content and c omposition, and developmental patterns. The comparison concerned CCR and CA D down-regulated lines (homozygous or heterozygous for the transgene) and t he hybrids resulting from the crossing of transgenic lines individually alt ered for CCR or CAD activities. Surprisingly, the crosses containing only o ne allele of each antisense transgene, exhibit a dramatic reduction of lign in content similar to the CCR down-regulated parent but, in contrast to thi s transgenic line, display a normal phenotype and only slight alterations o f the shape of the vessels. Qualitatively the lignin of the double transfor mant displays characteristics more like the wild type control than either o f the other transgenics. In the transgenics with a low lignin content, the transformations induced other biochemical changes involving polysaccharides , phenolic components of the cell wall and also soluble phenolics. These re sults show that the ectopic expression of a specific transgene may have a d ifferent impact depending on the genetic background and suggest that the tw o transgenes present in the crosses may operate synergistically to reduce t he lignin content. In addition, these data confirm that plants with a sever e reduction in lignin content may undergo normal development at least in co ntrolled conditions.