E. coli Fis Protein Insulates the cbpA Gene from Uncontrolled Transcription
| Autor: | Rajesh Shahapure, Amanda E. Rossiter, Remus T. Dame, Shivani S. Singh, Kiran Chintakayala, David C. Grainger |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
DNA
Bacterial Cancer Research lcsh:QH426-470 Transcription Genetic Molecular cloning Biology Biochemistry Microbiology DNA-binding protein 03 medical and health sciences chemistry.chemical_compound Model Organisms Transcription (biology) Factor For Inversion Stimulation Protein Escherichia coli Genetics Nucleoid Promoter Regions Genetic Molecular Biology Gene Genetics (clinical) Ecology Evolution Behavior and Systematics 030304 developmental biology 2. Zero hunger 0303 health sciences 030306 microbiology Escherichia coli Proteins Circular bacterial chromosome Genomics Gene Expression Regulation Bacterial Chromosomes Bacterial DNA-Binding Proteins lcsh:Genetics chemistry Carrier Proteins DNA Research Article Molecular Chaperones |
| Zdroj: | PLoS Genetics PLoS Genetics, Vol 9, Iss 1, p e1003152 (2013) |
| ISSN: | 1553-7404 |
| Popis: | The Escherichia coli curved DNA binding protein A (CbpA) is a poorly characterised nucleoid associated factor and co-chaperone. It is expressed at high levels as cells enter stationary phase. Using genetics, biochemistry, and genomics, we have examined regulation of, and DNA binding by, CbpA. We show that Fis, the dominant growth-phase nucleoid protein, prevents CbpA expression in growing cells. Regulation by Fis involves an unusual “insulation” mechanism. Thus, Fis protects cbpA from the effects of a distal promoter, located in an adjacent gene. In stationary phase, when Fis levels are low, CbpA binds the E. coli chromosome with a preference for the intrinsically curved Ter macrodomain. Disruption of the cbpA gene prompts dramatic changes in DNA topology. Thus, our work identifies a novel role for Fis and incorporates CbpA into the growing network of factors that mediate bacterial chromosome structure. Author Summary Compaction of chromosomal DNA is a fundamental process that impacts on all aspects of cellular biology. However, our understanding of chromosome organisation in bacteria is poorly developed. Since bacteria are amongst the most abundant living organisms on the planet, this represents a startling gap in our knowledge. Despite our lack of understanding, it has long been known that Escherichia coli, and other bacteria, radically re-model their chromosomes in response to environmental stress. This is most notable during periods of starvation, when the E. coli chromosome is super compacted. In dissecting the molecular mechanisms that control this phenomenon, we have found that regulatory cross-talk between DNA–organising proteins plays an essential role. Thus, the major DNA folding protein from growing E. coli inhibits production of the major chromosome organisers in starved cells. Our findings illustrate the highly dynamic nature of bacterial chromosomes. Thus, DNA topology, gene transcription, and chromosome folding proteins entwine to create a web of interactions that define the properties of the chromosome. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|