Seed dormancy release in Arabidopsis Cvi by dry after-ripening, low temperature, nitrate and light shows common quantitative patterns of gene expression directed by environmentally specific sensing
Article first published online: 25 APR 2007
The Plant Journal
Volume 51, Issue 1, pages 60–78, July 2007
How to Cite
Finch-Savage, W. E., Cadman, C. S. C., Toorop, P. E., Lynn, J. R. and Hilhorst, H. W. M. (2007), Seed dormancy release in Arabidopsis Cvi by dry after-ripening, low temperature, nitrate and light shows common quantitative patterns of gene expression directed by environmentally specific sensing. The Plant Journal, 51: 60–78. doi: 10.1111/j.1365-313X.2007.03118.x
- Issue published online: 3 MAY 2007
- Article first published online: 25 APR 2007
- Received 18 December 2006; revised 23 February 2007; accepted 6 March 2007.
Vol. 51, Issue 4, 738, Article first published online: 7 AUG 2007
- seed dormancy;
- transcriptome analysis;
- dry after-ripening;
The depth of seed dormancy can be influenced by a number of different environmental signals, but whether a common mechanism underlies this apparently similar response has yet to be investigated. Full-genome microarrays were used for a global transcript analysis of Arabidopsis thaliana Cape Verde Island accession seeds exposed to dry after-ripening (AR), or low temperature, nitrate and light when imbibed. Germination studies showed that the sensitivity of imbibed seeds to low temperature, nitrate and light was dependant upon the length of time spent AR following harvest. Seeds had an absolute requirement for light to complete dormancy release in all conditions, but this effect required an exposure to a prior dormancy relieving environment. Principal component analyses of the expression patterns observed grouped physiological states in a way that related to the depth of seed dormancy, rather than the type of environmental exposure. Furthermore, opposite changes in transcript abundance of genes in sets associated with dormancy, or dormancy relief through AR, were also related to the depth of dormancy and common to different environments. Besides these common quantitative changes, environment-specific gene expression patterns during dormancy relief are also described. For example, higher transcript abundance for genes linked to the process of nitrate accumulation, and nitrate reduction was associated with dormancy relief. The quantity of GA3ox1 transcripts increased during dormancy relief in all conditions, in particular when dormancy relief was completed by exposure to light. This contrasts with transcripts linked to abscisic acid (ABA) synthesis, which declined. The results are consistent with a role for the ABA/gibberellic acid balance in integrating dormancy-relieving environmental signals.