Please use this identifier to cite or link to this item:
|Scopus||Web of Science®||Altmetric|
|Title:||Quantitation of interactions between two DNA loops demonstrates loop domain insulation in E. coli cells|
|Citation:||Proceedings of the National Academy of Sciences of USA, 2014; 111(42):E4449-E4457|
|Publisher:||National Academy of Sciences|
|David G. Priest, Sandip Kumar, Yan Yan, David D. Dunlap, Ian B. Dodd, and Keith E. Shearwin|
|Abstract:||Eukaryotic gene regulation involves complex patterns of long-range DNA-looping interactions between enhancers and promoters, but how these specific interactions are achieved is poorly understood. Models that posit other DNA loops--that aid or inhibit enhancer-promoter contact--are difficult to test or quantitate rigorously in eukaryotic cells. Here, we use the well-characterized DNA-looping proteins Lac repressor and phage λ CI to measure interactions between pairs of long DNA loops in E. coli cells in the three possible topological arrangements. We find that side-by-side loops do not affect each other. Nested loops assist each other's formation consistent with their distance-shortening effect. In contrast, alternating loops, where one looping element is placed within the other DNA loop, inhibit each other's formation, thus providing clear support for the loop domain model for insulation. Modeling shows that combining loop assistance and loop interference can provide strong specificity in long-range interactions.|
|Keywords:||Lac repressor; lambda CI; statistical mechanical modeling; tethered particle motion|
|Appears in Collections:||Molecular and Biomedical Science publications|
Files in This Item:
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.