Li Y, Wu Y.
ASGSB Bull. 1995 Oct; 9: 54.
Division of Biology, Kansas State University, Manhattan, USA.
Seedlings grown under altered gravity conditions exhibit increased lateral root formation and ethylene production. To gain some insights about the involvement of auxin in these observed phenomena, we decided to examine expression of two auxin-inducible genes, SAUR and GH3, under altered gravity conditions. Transgenic seedlings that express SAUR promoter-GUS or GH3 promoter-GUS genes were grown on clinostats or a spaceflight (Spaceflight STS-63, February, 1995) for 7 days, and expression of SAUR and GH3 genes were determined by histochemical staining and fluorometric assay for GUS enzyme activity. Preliminary results indicate that expression of SAUR gene was 2 to 3 times higher in seedlings grown on clinostats than the stationary controls. Expression of GH3 gene was enhanced in cotyledons and root elongation region of seedlings grown on clinostats and the spaceflight as compared to the stationary or ground controls. If clinostat-grown seedlings were treated with exogenous auxin, expression of GH3 gene was induced to a significantly higher level than the stationary controls. These results suggest that seedlings grown under altered gravity conditions have elevated auxin levels or an increased sensitivity to auxin in tissues where SAUR and GH3 genes are expressed.
Publication Types:
Keywords:
- Cotyledon
- Ethylenes
- Gene Expression
- Gene Expression Regulation, Plant
- Indoleacetic Acids
- Plant Roots
- Plants, Genetically Modified
- Promoter Regions (Genetics)
- Rotation
- Seedling
- Space Flight
- Weightlessness
- Weightlessness Simulation
- ethylene
- genetics
Other ID:
UI: 102222775
From Meeting Abstracts