Analysis of in-vivo LacR-mediated gene repression based on the mechanics of DNA looping.

ABSTRACT: Interactions of E. coli lac repressor (LacR) with a pair of operator sites on the same DNA molecule can lead to the formation of looped nucleoprotein complexes both in vitro and in vivo. As a major paradigm for loop-mediated gene regulation, parameters such as operator affinity and spacing, repressor concentration, and DNA bending induced by specific or non-specific DNA-binding proteins (e.g., HU), have been examined extensively. However, a complete and rigorous model that integrates all of these aspects in a systematic and quantitative treatment of experimental data has not been available. Applying our recent statistical-mechanical theory for DNA looping, we calculated repression as a function of operator spacing (58-156 bp) from first principles and obtained excellent agreement with inde

SUBMITTER: Zhang Y 

PROVIDER: S-EPMC1762422 | biostudies-literature | 2006 Dec

REPOSITORIES: biostudies-literature