The gibberellin biosynthetic genes AtGA20ox1 and AtGA20ox2 act, partially redundantly, to promote growth and development throughout the Arabidopsis lifecycle

A - Papers appearing in refereed journals

Rieu, I., Ruiz-Rivero, O., Fernandez-Garcia, N., Griffiths, J., Powers, S. J., Gong, F., Linhartova, T., Eriksson, S., Nilsson, O., Thomas, S. G., Phillips, A. L. and Hedden, P. 2008. The gibberellin biosynthetic genes AtGA20ox1 and AtGA20ox2 act, partially redundantly, to promote growth and development throughout the Arabidopsis lifecycle. Plant Journal. 53 (3), pp. 488-504.

AuthorsRieu, I., Ruiz-Rivero, O., Fernandez-Garcia, N., Griffiths, J., Powers, S. J., Gong, F., Linhartova, T., Eriksson, S., Nilsson, O., Thomas, S. G., Phillips, A. L. and Hedden, P.
Abstract

The activity of the gibberellin (GA) biosynthetic enzymes GA 20-oxidases (GA20ox) is of particular importance in determining GA concentration in many plant species. In Arabidopsis these enzymes are encoded by a family of five genes: AtGA20ox1-AtGA20ox5. Transcript analysis indicated that they have different expression patterns and may thus participate differentially in GA-regulated developmental processes. We have used reverse genetics to determine the physiological roles of AtGA20ox1 and AtGA20ox2, the most highly expressed GA20ox genes during vegetative and early reproductive development. AtGA20ox1 and AtGA20ox2 act redundantly to promote hypocotyl and internode elongation, flowering time, elongation of anther filaments, the number of seeds that develop per silique and elongation of siliques, with AtGA200x1 making the greater contribution to internode and filament elongation, and AtGA20ox2 making the greater contribution to flowering time and silique length. Pollination of the double mutant with wild-type pollen indicated that the GA promoting silique elongation is of maternal origin. The ga20ox2 phenotype revealed that GA promotes the number of stem internodes that elongate upon bolting, and does so independently of its effect on internode elongation. Comparison of the phenotype of the double mutant with that of the highly GA-deficient ga1-3 mutant indicates that other GA20ox genes contribute to all the developmental processes examined, and, in some cases such as root growth and leaf expansion, make major contributions, as these processes were unaffected in the double mutant. In addition, the effects of the mutations are mitigated by the homeostatic mechanism that acts on expression of other GA dioxygenase and GID1 receptor genes.

KeywordsPlant Sciences
Year of Publication2008
JournalPlant Journal
Journal citation53 (3), pp. 488-504
Digital Object Identifier (DOI)doi:10.1111/j.1365-313X.2007.03356.x
PubMed ID18069939
Open accessPublished as non-open access
FunderBiotechnology and Biological Sciences Research Council
Funder project or codeCGI
MCB
ISSN09607412
PublisherWiley
Grant IDBBS/E/C/00004954
P19317

Permalink - https://repository.rothamsted.ac.uk/item/89yw1/the-gibberellin-biosynthetic-genes-atga20ox1-and-atga20ox2-act-partially-redundantly-to-promote-growth-and-development-throughout-the-arabidopsis-lifecycle

6 total views
0 total downloads
0 views this month
0 downloads this month