Overexpression of a fungal laccase gene induces nondehiscent anthers and morphological changes in flowers of transgenic tobacco
Laccases play important roles in the development of fruiting bodies and in lignin degradation by basidiomycetes. In this study, we present novel phenotypes of transgenic tobacco plants with a chimeric gene for fungal laccase under the control of the cauliflower mosaic virus 35S promoter. At the flowering stage, the transgenic plants that produced recombinant laccase had brownish anthers instead of the greenish anthers of wild-type plants. The brownish anthers exhibited male sterility with a nondehiscent phenotype at varying frequencies. The frequency of nondehiscence depended on the temperature at which plants were cultivated and it was higher at 24°C than at 29°C. The cell wall structures of transgenic anther tissues were almost the same as in the wild type, but the stomium was severely deformed, and abnormal components were apparent in cells of the endothecium and epidermis. Furthermore, the pattern of deposition of flavonoids in the transgenic anther epidermis differed from the wild-type pattern. The expression of laccase also induced other phenotypic changes in the flowers of transgenic plants, namely, increased petal number, fused and petaloid stamens, and doubling of floral organs. These results indicate that the ectopic expression of laccase influences various aspects of flower development.
Key wordsLaccase Nondehiscent anther Petaloid stamen Trametes versicolor Transgenic tobacco
Unable to display preview. Download preview PDF.
- 3.Leatham GF, Stahmann MA (1981) Studies on the laccase of Lentinus edodes: specificity, localization and association with the development of fruiting bodies. J Gen Microbiol 125:147–157Google Scholar
- 7.Galuszka P, Frébortová J, Luhová L, Bilyeu KD, English JT, Frébort I (2005) Tissue localization of cytokinin dehydrogenase in maze: possible involvement of quinone species generated from plant phenolics by other enzymatic systems in the catalytic reaction. Plant Cell Physiol 46:716–728CrossRefPubMedGoogle Scholar
- 20.Dence CW (1992) The determination of lignin. In: Lin SY, Dence CW (eds) Methods in lignin chemistry. Springer, Berlin Heidelberg New York, pp 33–61Google Scholar
- 22.Giusti MM, Wrolstad RE (2001) Characterization and measurement of anthocyanins by UV-visible spectroscopy. Curr Protocol Food Anal Chem (2001) F1.2.1–F1.2.13Google Scholar
- 28.Yasuor H, Abu-Abied M, Belausov E, Madmony A, Sadot E, Riov J, Rubin B (2006) Glyphosate-induced anther indehiscence in cotton is partially temperature dependent and involves cytoskeleton and secondary wall modifications and auxin accumulation. Plant Physiol 141:1306–1315CrossRefPubMedGoogle Scholar
- 38.Luo YH, Zuo Y, Su YQ, Ma HL (2008) Study on kinetic behaviors of the biocatalysis of laccase on oxidation of phenolic compounds — using catechol and epicatechin as model substrates. Chem Ind Forest Prod 28:13–17Google Scholar