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.

Abstract

An aspen lignin-specific O-methyltransferase (bi-OMT; S-adenosyl-L-methionine: caffeic acid/5-hydroxyferulic acid 3/5-O-methyltransferase, EC 2.1.1.68) antisense sequence in the form of a synthetic gene containing the cauliflower mosaic virus 35S gene sequences for enhancer elements, promoter and terminator was stably integrated into the tobacco genome and inherited in transgenic plants with a normal phenotype. Leaves and stems of the transgenes expressed the antisense RNA and the endogenous tobacco bi-OMT mRNA was suppressed in the stems. Bi-OMT activity of stems was decreased by an average of 29% in the four transgenic plants analyzed. Chemical analysis of woody tissue of stems for lignin building units indicated a reduced content of syringyl units in most of the transgenic plants, which corresponds well with the reduced activity of bi-OMT. Transgenic plants with a suppressed level of syringyl units and a level of guaiacyl units similar to control plants were presumed to have lignins of distinctly different structure than control plants. We concluded that regulation of the level of bi-OMT expression by an antisense mechanism could be a useful tool for genetically engineering plants with modified lignin without altering normal growth and development.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Base Sequence
  • Gene Expression Regulation, Plant
  • Lignin / analysis
  • Lignin / biosynthesis*
  • Methyltransferases / genetics*
  • Methyltransferases / metabolism
  • Molecular Sequence Data
  • Plant Leaves / chemistry
  • Plant Stems / chemistry
  • Plants, Genetically Modified
  • Plants, Toxic*
  • RNA, Antisense / genetics*
  • Tobacco / genetics*
  • Tobacco / metabolism
  • Trees / enzymology

Substances

  • RNA, Antisense
  • Lignin
  • Methyltransferases
  • caffeate O-methyltransferase