ISSN:
1573-5087
Keywords:
ornithine-δ-aminotransferase
;
proline accumulation
;
Oryza sativa
;
water stress
Source:
Springer Online Journal Archives 1860-2000
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
Abstract Proline is synthesized either from glutamate or from ornithine in plants. Relatively little is known about the contribution of the pathway from ornithine to proline biosynthesis. In this paper we investigated the contribution of ornithine-δ-aminotransterase (OAT), an enzyme responsible for ornithine pathway, to proline accumulation in water-stressed detached rice leaves. Although OAT activity increased with the increase of water stress duration, a pattern similar to that obtained for proline accumulation, the ornithine pathway in rice leaves seems to contribute little, if any, to proline accumulation under water stress condition. This conclusion was based on the observations that (a) gabaculine (50 μM), an inhibitor of OAT, inhibited about 75% OAT activity caused by water stress but reduced only 20% of proline content and (b) cycloheximide, a protein synthesis inhibitor, had no effect on OAT activity induced by water stress but significantly reduced proline accumulation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1006226732574
