Cyclic AMP as a modulator of polarity in polycistronic transcriptional units.
- 1 July 1979
- journal article
- research article
- Published by Proceedings of the National Academy of Sciences in Proceedings of the National Academy of Sciences
- Vol. 76 (7) , 3194-3197
- https://doi.org/10.1073/pnas.76.7.3194
Abstract
The degree of natural polarity in the lactose and galactose operons of Escherichia coli is affected by adenosine 3'',5''-cyclic monophosphate (cAMP). This effect, mediated by the cAMP receptor protein, is exerted at sites distinct from the promoter. Experiments performed with a mutant bearing a thermosensitive rho factor activity indicate that cAMP relieves polarity by interfering with transcription termination. Conflicting results in the literature concerning the role of cAMP receptor protein and cAMP in galactose operon expression can be reconciled by the finding that cAMP stimulates the expression of operator distal genes without significantly affecting the proximal genes. It appears necessary to reevaluate the classification of the galactose operon as exhibiting cAMP-mediated catabolite repression at the level of transcription initiation.This publication has 20 references indexed in Scilit:
- Translational control of transcription termination at the attenuator of the Escherichia coli tryptophan operon.Proceedings of the National Academy of Sciences, 1978
- Dual control for transcription of the galactose operon by cyclic AMP and its receptor protein at two interspersed promotersCell, 1977
- Isolation and characterization of conditional lethal mutants of Escherichia coli defective in transcription termination factor rho.Proceedings of the National Academy of Sciences, 1976
- Deletion of the Escherichia coli crp GeneJournal of Bacteriology, 1975
- Bearing of some recent results on the mechanisms of polarity and messenger RNA stabilityMolecular Genetics and Genomics, 1974
- Relief of polarity in DNA-dependent cell-free synthesis of enzymes of the galactose operon of Escherichia coliMolecular Genetics and Genomics, 1972
- In Vitro Transcription of the Gal Operon Requires Cyclic Adenosine Monophosphate and Cyclic Adenosine Monophosphate Receptor ProteinJournal of Biological Chemistry, 1971
- DNA-dependent in vitro synthesis of enzymes of the galactose operon of Escherichia coliMolecular Genetics and Genomics, 1971
- Synthesis, utilization and degradation of lactose operon mRNA in Escherichia coliJournal of Molecular Biology, 1967
- Mécanismes régulateurs dans la biosynthèse des enzymes du métabolisme du galactose chez Escherichia coli K12Journal of Molecular Biology, 1963