DNA sequence-dependent mechanics and protein-assisted bending in repressor-mediated loop formation.

ABSTRACT: As the chief informational molecule of life, DNA is subject to extensive physical manipulations. The energy required to deform double-helical DNA depends on sequence, and this mechanical code of DNA influences gene regulation, such as through nucleosome positioning. Here we examine the sequence-dependent flexibility of DNA in bacterial transcription factor-mediated looping, a context for which the role of sequence remains poorly understood. Using a suite of synthetic constructs repressed by the Lac repressor and two well-known sequences that show large flexibility differences in vitro, we make precise statistical mechanical predictions as to how DNA sequence influences loop formation and test these predictions using in vivo transcription and in vitro single-molecule assays. Surprisingly, s

SUBMITTER: Boedicker JQ 

PROVIDER: S-EPMC3915735 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature