Arabidopsis ALS genes

Figure 2. Assays of tobacco transformed with Arabidopsis ALS genes. Tobacco containing either the herbicide sensitive (S) or resistant (R) ALS gene was tested for the ability of transformed callus to grow in the presence of herbicide (slashed boxes) and the herbicide resistance of enzyme activity in plant extracts (solid boxes). Each measurement is expressed as a percentage of the value that was obtained in the absence of herbicide.

In the second approach, herbicide-resistance mutations in the Arabidopsis ALS gene were studied in E. coli. To do this, wild type and mutant Arabidopsis genes were functionally expressed in E. coli, such that the plant genes complemented a branched chain amino acid auxotrophy in the bacteria (Smith et al. 1989, PNAS in press). ALS enzyme assays on extracts prepared from E. coli expressing the mutant Arabidopsis gene indicated that the mutant enzyme is resistant to sulfonylurea herbicides but is sensitive to the imidazolinone herbicide imazaquin. This selective... 

Franke, R. et al.. The Arabidopsis REFS gene encodes the 3-hydroxylase of phenylpropanoid metabolism. Plant J., 30, 33, 2002. 

Abrahams, S. et al., The Arabidopsis TDS4 gene encodes leucoanthocyanidin dioxygenase (LDOX) and is essential for proanthocyanidin synthesis and vacuole development. Plant Cell, 35, 624, 2003. 

Giraudat, J. et al., Isolation of the Arabidopsis ABI3 gene by positional cloning. Plant Cell, 4,1251, 1992. 

These cloned Arabidopsis and tobacco ALS genes have been used as hybridization probes to isolate ALS genes from other crop species and to isolate ALS genes from plants selected for resistance to sulfonylurea herbicides. 

Mezzari MP et al., Gene expression and microscopic analysis of Arabidopsis exposed to chloroacetanilide herbicides and explosive compounds. A phytoremediation approach, Plant Physiol., 138, 858, 2005. 

Mahonen, A. P., et al. 2000. A novel two-component hybrid molecule regulates vascular morphogenesis of the Arabidopsis root. Genes Devel 14 2938-2943. 

A. Sakurai, T. Yokata et al. (1998). Transcription of the Arabidopsis CPD gene, encoding a steroidogenic cytochrome P450, is negatively controlled by brassinosteroids. Plant J. 14, 593-602. 

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