Biomaterial Database

Single-molecule analysis of SSB dynamics on single-stranded DNA. 2012

Ruobo Zhou, and Taekjip Ha

Department of Physics and Center for the Physics of Living Cells, University of Illinois, Urbana-Champaign, IL, USA. ruobo.zhou@gmail.com

SSB proteins bind to and control the accessibility of single-stranded (ss) DNA generated as a transient intermediate during a variety of cellular processes. For subsequent DNA processing, however, SSB needs to be removed and yield to other proteins while avoiding ssDNA exposure to nucleases. Using single-molecule two- and three-color fluorescence resonance energy transfer (FRET) and fluorescence-force spectroscopy, we recently showed that the SSB/DNA complex is a highly dynamic system and SSB functions as a sliding platform that migrates on ssDNA for recruiting other proteins in DNA repair, replication, and recombination. Here, we present the activity assays in detail for observing the transitions between different SSB binding modes and SSB diffusion on ssDNA in real time by using single-molecule FRET microscopy and for studying how mechanical forces regulate SSB-DNA interactions using fluorescence-force spectroscopy. These single-molecule approaches are generally applicable to many other protein-nucleic acid systems.

UI	MeSH Term	Description	Entries
D008967	Molecular Biology	A discipline concerned with studying biological phenomena in terms of the chemical and physical interactions of molecules.	Biochemical Genetics,Biology, Molecular,Genetics, Biochemical,Genetics, Molecular,Molecular Genetics,Biochemical Genetic,Genetic, Biochemical,Genetic, Molecular,Molecular Genetic
D004268	DNA-Binding Proteins	Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.	DNA Helix Destabilizing Proteins,DNA-Binding Protein,Single-Stranded DNA Binding Proteins,DNA Binding Protein,DNA Single-Stranded Binding Protein,SS DNA BP,Single-Stranded DNA-Binding Protein,Binding Protein, DNA,DNA Binding Proteins,DNA Single Stranded Binding Protein,DNA-Binding Protein, Single-Stranded,Protein, DNA-Binding,Single Stranded DNA Binding Protein,Single Stranded DNA Binding Proteins
D004277	DNA, Single-Stranded	A single chain of deoxyribonucleotides that occurs in some bacteria and viruses. It usually exists as a covalently closed circle.	Single-Stranded DNA,DNA, Single Stranded,Single Stranded DNA
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D013050	Spectrometry, Fluorescence	Measurement of the intensity and quality of fluorescence.	Fluorescence Spectrophotometry,Fluorescence Spectroscopy,Spectrofluorometry,Fluorescence Spectrometry,Spectrophotometry, Fluorescence,Spectroscopy, Fluorescence
D029968	Escherichia coli Proteins	Proteins obtained from ESCHERICHIA COLI.	E coli Proteins
D031541	Fluorescence Resonance Energy Transfer	A type of FLUORESCENCE SPECTROSCOPY using two FLUORESCENT DYES with overlapping emission and absorption spectra, which is used to indicate proximity of labeled molecules. This technique is useful for studying interactions of molecules and PROTEIN FOLDING.	Forster Resonance Energy Transfer