Related Experiment Video
Updated: Jul 20, 2026

Combined Immunofluorescence and DNA FISH on 3D-preserved Interphase Nuclei to Study Changes in 3D Nuclear Organization
Published on: February 3, 2013
Location, degree, and direction of DNA bending associated with the Hin recombinational enhancer sequence and
D Perkins-Balding1, D P Dias, A C Glasgow
1Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, Georgia 30322, USA.
Abstract:
The Fis protein of Escherichia coli and Salmonella typhimurium stimulates several site-specific DNA recombination reactions, as well as transcription of a number of genes. Fis binds to a 15-bp core recognition sequence and induces DNA bending. Mutations in Fis which alter its ability to bend DNA have been shown to reduce the stimulatory activity of Fis in both site-specific recombination and transcription systems. To examine the role of DNA bending in the activity of the Fis-recombinational enhancer complex in Hin-mediated site-specific DNA inversion, we have determined the locations, degrees, and directions of DNA bends associated with the recombinational enhancer and the Fis-enhancer complex. Circular-permutation assays demonstrated that a sequence-directed DNA bend is associated with the Fis binding sites in the proximal and distal domains of the recombinational enhancer. Binding of Fis to its core recognition sequence significantly increases the degree of DNA bending associated with the proximal and distal domains. The degree of DNA bending induced by Fis binding depended on the DNA sequences flanking the core Fis binding site, with angles ranging from 42 to 69 degrees. Phasing analyses indicate that both the sequence-directed and the Fis-induced DNA bends associated with the proximal and distal domains face the minor groove of the DNA helix at the center of the Fis binding site. The positions and directions of DNA bends associated with the Fis-recombinational complex support a direct role for Fis-induced DNA bending in assembly of the active invertasome.
More Related Videos
11:12Determination of the Optimal Chromosomal Location(s) for a DNA Element in Escherichia coli Using a Novel Transposon-mediated Approach
Published on: September 11, 2017
07:55Detection of Homologous Recombination Intermediates via Proximity Ligation and Quantitative PCR in Saccharomyces cerevisiae
Published on: September 11, 2022
Related Concept Videos
The DNA Replication Fork
Homologous Recombination
Conservative Site-specific Recombination and Phase Variation
The recognition sites for Cre recombinase called LoxP...
Cis-regulatory Sequences
Cooperative Binding of Transcription Regulators
FISH - Fluorescent In-situ Hybridization