Article ; Online: Transcription-driven DNA supercoiling counteracts H-NS-mediated gene silencing in bacterial chromatin.
2024 Volume 15, Issue 1, Page(s) 2787
Abstract: In all living cells, genomic DNA is compacted through interactions with dedicated proteins and/or the formation of plectonemic coils. In bacteria, DNA compaction is achieved dynamically, coordinated with dense and constantly changing transcriptional ... ...
| Abstract | In all living cells, genomic DNA is compacted through interactions with dedicated proteins and/or the formation of plectonemic coils. In bacteria, DNA compaction is achieved dynamically, coordinated with dense and constantly changing transcriptional activity. H-NS, a major bacterial nucleoid structuring protein, is of special interest due to its interplay with RNA polymerase. H-NS:DNA nucleoprotein filaments inhibit transcription initiation by RNA polymerase. However, the discovery that genes silenced by H-NS can be activated by transcription originating from neighboring regions has suggested that elongating RNA polymerases can disassemble H-NS:DNA filaments. In this study, we present evidence that transcription-induced counter-silencing does not require transcription to reach the silenced gene; rather, it exerts its effect at a distance. Counter-silencing is suppressed by introducing a DNA gyrase binding site within the intervening segment, suggesting that the long-range effect results from transcription-driven positive DNA supercoils diffusing toward the silenced gene. We propose a model wherein H-NS:DNA complexes form in vivo on negatively supercoiled DNA, with H-NS bridging the two arms of the plectoneme. Rotational diffusion of positive supercoils generated by neighboring transcription will cause the H-NS-bound negatively-supercoiled plectoneme to "unroll" disrupting the H-NS bridges and releasing H-NS. |
|---|---|
| MeSH term(s) | Chromatin/metabolism ; DNA-Binding Proteins/metabolism ; Bacterial Proteins/genetics ; Bacterial Proteins/metabolism ; Bacteria/genetics ; DNA-Directed RNA Polymerases/genetics ; DNA-Directed RNA Polymerases/metabolism ; DNA/metabolism ; Gene Silencing ; Gene Expression Regulation, Bacterial ; DNA, Bacterial/genetics ; DNA, Bacterial/metabolism ; Transcription, Genetic |
| Chemical Substances | Chromatin ; DNA-Binding Proteins ; Bacterial Proteins ; DNA-Directed RNA Polymerases (EC 2.7.7.6) ; DNA (9007-49-2) ; DNA, Bacterial |
| Language | English |
| Publishing date | 2024-03-30 |
| Publishing country | England |
| Document type | Journal Article |
| ZDB-ID | 2553671-0 |
| ISSN | 2041-1723 ; 2041-1723 |
| ISSN (online) | 2041-1723 |
| ISSN | 2041-1723 |
| DOI | 10.1038/s41467-024-47114-w |
| Database | MEDical Literature Analysis and Retrieval System OnLINE |
More links
Kategorien
Order via subito
This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.