Abstract
Auxin [α-naphthaleneacetic acid (NAA) or indole-3-acetic acid (IAA)] can induce the expression of two lipoxygenases (LOXs) in cultured immature zygotic embryo cotyledons of soybean (Glycine max L.). One of the IAA/NAA- induced LOX isozymes in cultured embryo cotyledons has been demonstrated to be seedling LOX4 (pI 5.09) and another appears to be LOX5 (pI 5.23). The effects of jasmonic acid (JA), methyl jasmonate (MJ), abscisic acid (ABA) and triiodobenzoic acid (TIBA) on the expression of NAA-induced LOXs were investigated in the cultured embryo cotyledons. Among tested plant regulators, only NAA can induce the expression of LOX4 and LOX5, whereas MJ, JA or ABA did not induce LOX expression in the absence of NAA. However combination of NAA with JA significantly increases the expression of NAA- induced LOXs compared with NAA alone. TIBA, an inhibitor of auxin transport, blocks the expressions of the NAA-induced LOXs in the cultured embryos. Immunogold labeling showed that NAA-induced LOXs are located in vacuoles. Our results suggest that auxin may directly or indirectly trigger the expression of soybean seedling LOXs during soybean germination. We also report that seedling LOX4 and/or LOX5 are located in vacuoles.
| Original language | English |
|---|---|
| Pages (from-to) | 147-153 |
| Number of pages | 7 |
| Journal | Plant Science |
| Volume | 148 |
| Issue number | 2 |
| DOIs | |
| State | Published - Oct 29 1999 |
Bibliographical note
Funding Information:We thank Ms Yuan Sun and Mr Zhiqiang Yu for their excellent assistance in electron microscope, Dr Nordin for use of an electron microscope and Dr Wennuan Liu for help with soybean tissue culturing. We also thank Dr K. Kitamura for the soybean LOX mutant. This work was supported by the USDA (grant #9701487) and the Kentucky Agricultural Experiment Station
Keywords
- Auxin
- Glycine max
- Lipoxygenase
- Subcellular localization
ASJC Scopus subject areas
- Genetics
- Agronomy and Crop Science
- Plant Science