Positive Control of Translation in Organellar Genetic Systems
The expression of genes in the mitochondria and chloroplasts of eucaryotic cells is, in many cases, modulated in response to environmental factors. In the case of yeast mitochondria, gene expression is lowered in the absence of oxygen (Woodrow and Schatz 1979) and/or in the presence of glucose (Falcone et al. 1983). In the case of chloroplasts, gene expression is dependent on the presence of light, in most cases (Mullet 1988). In both of these organellar systems, available genetic and physiological evidence indicates that the expression of many genes is dependent upon mRNA-specific translational activators, and that these activators may play a role in modulating gene expression.
KeywordsGlycerol Maize Codon Polypeptide Galactose
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