type	Journal Article
authors	Radwanski, E. R.; Barczak, A. J.; Last, R. L.
title	Characterization of tryptophan synthase alpha subunit mutants of Arabidopsis thaliana
journal	Mol Gen Genet
Activity	4.2.1.20
ui	97156941
year	(1996)
volume	253
number	3
pages	353-61.
keywords	Arabidopsis/*enzymology/genetics
abstract	Three mutations in the Arabidopsis thaliana gene encoding the alpha subunit of tryptophan synthase were isolated by selection for resistance to 5-methylanthranilate or 5-fluoroindole, toxic analogs of tryptophan pathway intermediates. Plants homozygous for trp3-1 and trp3- 2 are light-conditional tryptophan auxotrophs, while trp3-100 is a more leaky mutant. Genetic complementation crosses demonstrated that the three mutations are allelic to each other, and define a new complementation group. All three mutants have decreased steady-state levels of tryptophan synthase alpha protein, and the trp3-100 polypeptide exhibits altered electrophoretic mobility. All three mutations were shown to be in the TSA1 (tryptophan synthase alpha subunit) structural gene by several criteria. Firstly, the trp3-1 mutation is linked to TSA1 on the bottom of chromosome 3. Secondly, the trp3-1 mutation was complemented when transformed with the wild-type TSA1 gene. Finally, DNA sequence analysis of the TSA1 gene revealed a single transition mutation in each trp3 mutant.
last changed	2002/11/12 16:17