Abstract
Successful execution of germination program greatly depends on the seeds’ oxidative homeostasis. We recently identified new roles for the H2O2-reducing enzyme ascorbate peroxidase 6 (APX6) in germination control and seeds’ stress tolerance. APX6 replaces APX1 as the dominant APX in dry seeds, and its loss-of-function results in reduced germination due to over accumulation of ROS and oxidative damage. Metabolic analyses in dry apx6 seeds, revealed altered homeostasis of primary metabolites including accumulation of TCA cycle metabolites, ABA and auxin, supporting a novel role for APX6 in regulating cellular metabolism. Increased sensitivity of apx6 mutants to ABA or IAA in germination assays indicated impaired perception of these signals. Relative suppression of ABI3 and ABI5 expression, and induction of ABI4, suggested the activation of a signaling route inhibiting germination in apx6 seeds that is independent of ABI3. Here we provide additional evidence linking ABI4 with ABA- and auxin-controlled inhibition of germination and suggest a hypothetical model for the role of APX6 in the regulation of the crosstalk between these hormones and ROS.
Original language | English |
---|---|
Article number | e976489 |
Pages (from-to) | e976489-1-e976489-4 |
Journal | Plant Signaling and Behavior |
Volume | 9 |
Issue number | 12 |
DOIs | |
State | Published - 31 Dec 2014 |
Bibliographical note
Publisher Copyright:© Changming Chen, Shir Twito, and Gad Miller.
Funding
This work was supported by the MarieCurie Actions-International Career. Integration Grant (grant no. 293999), the Israel Science Foundation (grant no. 938/ 11) and the Binational Agricultural Research & Development Fund (project IS-4652-13 R).
Funders | Funder number |
---|---|
United States - Israel Binational Agricultural Research and Development Fund | IS-4652-13 R |
Office of Career, Technical, and Adult Education | |
Seventh Framework Programme | 293999 |
Israel Science Foundation | 938/ 11 |
Keywords
- ABA
- ABI3
- ABI4
- ABI5
- APX
- Ascorbate peroxidase
- Auxin
- Germination
- ROS
- Redox
- Seed