Gachotte D, et al. (1995) An Arabidopsis mutant deficient in sterol biosynthesis: heterologous complementation by ERG 3 encoding a delta 7-sterol-C-5-desaturase from yeast. Plant J 8(3):407-16
Abstract: The mutant STE 1 was isolated by screening an ethylmethane sulfonate (EMS)-mutagenized population of Arabidopsis thaliana which consisted of 22,000 M2 plants divided into 1100 pools of 20 plants by gas chromatography of sterols extracted from small leaf samples. STE 1 was characterized by the accumulation of three delta 7-sterols concomitantly with the decrease of the three corresponding delta 5-sterols which are the end products of the sterol pathway in wild-type leaves. The structure of these delta 7-sterols was determined after two steps of purification on HPLC, by gas chromatography coupled with mass spectrometry (GC-MS) and proton nuclear magnetic resonance spectrometry (1H-NMR). The accumulation of delta 7-sterols suggested that the mutant is deficient in the activity of the delta 7-sterol-C-5-desaturase. Genetic analysis showed that the accumulation of delta 7-sterols was due to a single recessive nuclear mutation. The mutant line STE 1 was backcrossed four times to the wild-type. The resulting STE 1 plants had wild-type morphology and set seeds normally, suggesting that the delta 7-sterols in STE 1 are good surrogates of physiologically active delta 5-sterols to sustain normal development. STE 1 roots were transformed with the Saccharomyces cerevisiae ERG 3 gene encoding the delta 7-sterol-C-5-desaturase under the control of the CaMV 35S promoter. Seven transgenic STE 1 root-derived calli showed an increase in delta 5-sterols and a concomitant decrease in delta 7-sterols in comparison with STE 1 untransformed root-derived calli. Northern blot analysis using the ERG 3 probe showed a strong expression of ERG 3 in three of the seven transgenic calli. These results suggest that the accumulation of delta 7-sterols in the STE 1 mutant is due to a deficiency of the delta 7-sterol-C-5-desaturation step in the plant sterol biosynthesis pathway.
|Status: Published||Type: Journal Article||PubMed ID: 7550378|
Topics addressed in this paper
- To find other papers on a gene and topic, click on the colored ball in the appropriate box.
- displays other papers with information about that topic for that gene.
- displays other papers in SGD that are associated with that topic.
The topic is addressed in these papers but does not describe a specific gene or chromosomal feature.
- To go to the Locus page for a gene, click on the gene name.
|Topics||Genes linked to topics|