Related Experiment Video
Updated: Jun 12, 2026

Studying DNA Looping by Single-Molecule FRET
Published on: June 28, 2014
Mechanical and structural properties of YOYO-1 complexed DNA
Katrin Günther1, Michael Mertig, Ralf Seidel
1BioNanotechnology and Structure Formation Group, Department of Chemistry and Food Chemistry, Biotechnology Center, Technische Universität Dresden, D-01062 Dresden, Germany.
Abstract:
YOYO-1 is a fluorescent dye widely used for probing the statistical-mechanical properties of DNA. However, currently contradicting data exist how YOYO-1 binding alters the DNA structure and rigidity. Here, we systematically address this problem using magnetic tweezers. Remarkably, we find that the persistence length of DNA remains constant independent of the amount of bound YOYO-1, which contrasts previous assumptions. While the ionic conditions can considerably alter the stability of YOYO-1 binding, the DNA bending rigidity seems not to be affected. We furthermore determine important structural parameters such as the binding site size, the elongation, as well as the untwisting angle per bound YOYO-1 molecule. We expect that our assay, in which all the parameters are determined within a single experiment, will be beneficial for a large range of other DNA binding drugs.
Related Concept Videos
The Nucleosome
In a chromosome, DNA is wound twice around a protein complex called a histone octamer core, which consists of 8 histone proteins. This...
The Nucleosome
DNA is wound twice around a protein complex called histone core, that consist of 8 histone proteins. This complex...
Nucleic Acid Structure
DNA Structure
DNA has a double-helix structure. The...
DNA Topoisomerases
Types and Mechanism of action
Topoisomerases are divided into two main types. Type I...
Single-Strand DNA Binding Proteins
DNA Helicases
