DNA twist, flexibility and transcription of the osmoregulated proU promoter of Salmonella typhimurium
| Autor: | Bart J.A.M. Jordi, Christopher F. Higgins, Tom Owen-Hughes, Christopher S.J. Hulton |
|---|---|
| Rok vydání: | 1995 |
| Předmět: |
Aminocoumarins
DNA Bacterial Salmonella typhimurium Amino Acid Transport Systems Transcription Genetic Molecular Sequence Data Mutant Biology General Biochemistry Genetics and Molecular Biology Structure-Activity Relationship symbols.namesake chemistry.chemical_compound Bacterial Proteins Coumarins Osmotic Pressure Transcription (biology) Topoisomerase II Inhibitors Promoter Regions Genetic skin and connective tissue diseases Molecular Biology Writhe Binding Sites Base Sequence General Immunology and Microbiology DNA Superhelical General Neuroscience Linking number Promoter DNA-Directed RNA Polymerases Gene Expression Regulation Bacterial Molecular biology In vitro Cell biology chemistry Mutation symbols Nucleic Acid Conformation DNA supercoil sense organs Carrier Proteins DNA Research Article |
| Zdroj: | The EMBO Journal. 14:5690-5700 |
| ISSN: | 0261-4189 |
| DOI: | 10.1002/j.1460-2075.1995.tb00256.x |
| Popis: | Transcription from many bacterial promoters is sensitive to the level of DNA supercoiling. We have investigated the mechanism by which environmentally induced changes in DNA supercoiling might regulate transcription. For the proU promoter of Salmonella typhimurium, osmotically induced changes in DNA topology appear to play a primary regulatory role. Changes in DNA supercoiling (linking number; delta Lk) are partitioned into changes in the winding of the strands of the double helix about themselves (twist; delta Tw) and/or elastic deformations or flexibility of the DNA helix (writhe; delta Wr). Mutations of the proU promoter were isolated in vivo, or generated in vitro, which altered the spacing between the -10 and -35 motifs. Studies on these mutant promoters, both in vivo and in vitro, exclude models in which changes in DNA twist play a regulatory role. Instead, our data suggest that increased DNA flexibility, reflecting the osmotically induced increase in negative supercoiling of DNA, is required for promoter activation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|