Back to Search
Start Over
Antisense-transformation reveals novel roles for class I beta-1,3-glucanase in tobacco seed after-ripening and photodormancy.
- Source :
-
Journal of experimental botany [J Exp Bot] 2001 Sep; Vol. 52 (362), pp. 1753-9. - Publication Year :
- 2001
-
Abstract
- Little is known about the molecular basis for seed dormancy, after-ripening, and radicle emergence through the covering layers during germination. In tobacco, endosperm rupture occurs after testa rupture and is the limiting step in seed germination. Class I beta-1,3-glucanase (betaGLU I), which is induced in the micropylar endosperm just prior to its penetration by the radicle, is believed to help weaken the endosperm wall. Evidence is presented here for a second site of betaGLU I action during after-ripening. Tobacco plants were transformed with antisense betaGLU I constructs with promoters thought to direct endosperm-specific expression. Unexpectedly, these transformants were unaffected in endosperm rupture and did not exhibit reduced betaGLU I expression during germination. Nevertheless, antisense betaGLU I transformation delayed the onset of testa rupture in light-imbibed, after-ripened seeds and inhibited the after-ripening-mediated release of photodormancy. It is proposed that betaGLU I expression in the dry seed contributes to the after-ripening-mediated release of seed dormancy.
- Subjects :
- Abscisic Acid
Antisense Elements (Genetics)
Gene Expression Regulation, Enzymologic
Gene Expression Regulation, Plant
Germination genetics
Germination physiology
Glucan 1,3-beta-Glucosidase
Photochemistry
Plants, Genetically Modified
Promoter Regions, Genetic
Seeds enzymology
Seeds genetics
Nicotiana genetics
Transformation, Genetic
beta-Glucosidase genetics
Nicotiana enzymology
beta-Glucosidase physiology
Subjects
Details
- Language :
- English
- ISSN :
- 0022-0957
- Volume :
- 52
- Issue :
- 362
- Database :
- MEDLINE
- Journal :
- Journal of experimental botany
- Publication Type :
- Academic Journal
- Accession number :
- 11520863
- Full Text :
- https://doi.org/10.1093/jexbot/52.362.1753