type	Journal Article
authors	Barroso, C.; Romero, L. C.; Cejudo, F. J.; Vega, J. M.; Gotor, C.
title	Salt-specific regulation of the cytosolic O-acetylserine(thiol)lyase gene from Arabidopsis thaliana is dependent on abscisic acid
journal	Plant Mol Biol
Activity	2.5.1.47
ui	99408273
year	(1999)
volume	40
number	4
pages	729-36.
keywords	Abscisic Acid/*pharmacology
abstract	The expression of Atcys-3A gene coding for cytosolic O- acetylserine(thiol)lyase, a key enzyme in cysteine biosynthesis, from Arabidopsis thaliana is significantly induced by exposure to salt and heavy-metal stresses. Addition of NaCl to mature plants induced a rapid accumulation of the mRNA throughout the leaf lamina and roots, and later on in stems, being mainly restricted to vascular tissues. The salt-specific regulation of Atcys-3A was also mediated by abscisic acid (ABA) since: (1) exogenous addition of ABA to the culture medium mimicked the salt-induced plant response by raising the level of Atcys- 3A transcript, and (2) Arabidopsis mutants aba-1 and abi2-1 were not able to respond to NaCl. Our results suggest that a high rate of cysteine biosynthesis is required in Arabidopsis under salt stress necessary for a plant protection or adaptation mechanism. This hypothesis was supported by the observation that intracellular levels of cysteine and glutathione increased up to 3-fold after salt treatment.
last changed	2003/03/17 14:53