Name: application of stopped-flow kinetics methods to investigate the mechanism of action of a dna repair protein
Uploaded: 2010-03-31T17:00:00
Description: Watch this Scientific Journal Video about Application of Stopped-flow Kinetics Methods to Investigate the Mechanism of Action of a DNA Repair Protein at JoVE.com

This work was supported by an NSF CAREER Award (M.M.H), a Barry M. Goldwater scholarship (F.N.B) and an ASBMB Undergraduate Research Award (C.W.D). The clone for over-expression of PBP was kindly provided by Dr. Martin Webb (MRC, UK).

A. Measurement of Msh2-Msh6 DNA Binding Kinetics
1. Sample preparation for the Msh2-Msh6 DNA binding kinetics experiment
Preparation of reagents for a fluorescence-based kinetic DNA binding experiment on a stopped-flow is similar to that for an equilibrium experiment on a fluorometer. Indeed equilibrium binding analysis should be performed first to estimate the dissociation constant (KD) for the interaction in order to optimize reaction conditions f...

<ol>
	<li>Johnson, K. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Advances+in+transient-state+kinetics.">Advances in transient-state kinetics.</a> Curr Opin Biotechnol. 9 (1), 87-89 (1998).</li><li>Johnson, K. A. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Kinetic analysis of macromolecules. , (2003).</li><li>Obmolova, G., Ban, C., Hsieh, P., Yang, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Crystal+structures+of+mismatch+repair+protein+MutS+and+its+complex+with+a+substrate+DNA.">Crystal structures of mismatch repair protein MutS and its complex with a substrate DNA.</a> Nature. 407 (6805), 703-710 (2000).</li><li>Lamers, M. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+crystal+structure+of+DNA+mismatch+repair+protein+MutS+binding+to+a+G+x+T+mismatch.">The crystal structure of DNA mismatch repair protein MutS binding to a G x T mismatch.</a> Nature. 407 (6805), 711-717 (2000).</li><li>Warren, J. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structure+of+the+human+MutSalpha+DNA+lesion+recognition+complex.">Structure of the human MutSalpha DNA lesion recognition complex.</a> Mol Cell. 26 (4), 579-592 (2007).</li><li>Kunkel, T. A. &. a. m. p. ;. a. m. p., Erie, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> DNA Mismatch Repair. Annu Rev Biochem. 74, 681-710 (2005).</li><li>Jiricny, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+multifaceted+mismatch-repair+system.">The multifaceted mismatch-repair system.</a> Nat Rev Mol Cell Biol. 7 (5), 335-346 (2006).</li><li>Hsieh, P., Yamane, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=DNA+mismatch+repair:+Molecular+mechanism,+cancer,+and+ageing.">DNA mismatch repair: Molecular mechanism, cancer, and ageing.</a> Mech Ageing Dev. 129 (7-8), 391-407 (2008).</li><li>Jacobs-Palmer, E., Hingorani, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effects+of+nucleotides+on+MutS-DNA+binding+kinetics+clarify+the+role+of+MutS+ATPase+activity+in+mismatch+repair.">The effects of nucleotides on MutS-DNA binding kinetics clarify the role of MutS ATPase activity in mismatch repair.</a> J Mol Biol. 366 (4), 1087-1098 (2007).</li><li>Antony, E., Khubchandani, S., Chen, S., Hingorani, M. M., M, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Contribution+of+Msh2+and+Msh6+subunits+to+the+asymmetric+ATPase+and+DNA+mismatch+binding+activities+of+Saccharomyces+cerevisiae+Msh2-Msh6+mismatch+repair+protein.">Contribution of Msh2 and Msh6 subunits to the asymmetric ATPase and DNA mismatch binding activities of Saccharomyces cerevisiae Msh2-Msh6 mismatch repair protein.</a> DNA Repair (Amst). 5 (2), 153-162 (2006).</li><li>Antony, E., Hingorani, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mismatch+recognition-coupled+stabilization+of+Msh2-Msh6+in+an+ATP-bound+state+at+the+initiation+of+DNA+repair.">Mismatch recognition-coupled stabilization of Msh2-Msh6 in an ATP-bound state at the initiation of DNA repair.</a> Biochemistry. 42 (25), 7682-7693 (2003).</li><li>Finkelstein, J., Antony, E., Hingorani, M. M., O'Donnell, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Overproduction+and+analysis+of+eukaryotic+multiprotein+complexes+in+Escherichia+coli+using+a+dual-vector+strategy.">Overproduction and analysis of eukaryotic multiprotein complexes in Escherichia coli using a dual-vector strategy.</a> Anal Biochem. 319 (1), 78-87 (2003).</li><li>Zhai, J., Hingorani, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=S.+cerevisiae+Msh2-Msh6+DNA+binding+kinetics+reveal+a+mechanism+of+targeting+sites+for+DNA+mismatch+repair.">S. cerevisiae Msh2-Msh6 DNA binding kinetics reveal a mechanism of targeting sites for DNA mismatch repair.</a> Proc Natl Acad Sci U S A. 107 (2), 680-685 (2010).</li><li>Brune, M., Hunter, J. L., Corrie, J. E., Webb, M. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Direct,+real-time+measurement+of+rapid+inorganic+phosphate+release+using+a+novel+fluorescent+probe+and+its+application+to+actomyosin+subfragment+1+ATPase.">Direct, real-time measurement of rapid inorganic phosphate release using a novel fluorescent probe and its application to actomyosin subfragment 1 ATPase.</a> Biochemistry. 33 (27), 8262-8271 (1994).</li><li>Brune, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanism+of+inorganic+phosphate+interaction+with+phosphate+binding+protein+from+Escherichia+coli.">Mechanism of inorganic phosphate interaction with phosphate binding protein from Escherichia coli.</a> Biochemistry. 37 (29), 10370-10380 (1998).</li><li>Antony, E., Hingorani, M. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Asymmetric+ATP+binding+and+hydrolysis+activity+of+the+Thermus+aquaticus+MutS+dimer+is+key+to+modulation+of+its+interactions+with+mismatched+DNA.">Asymmetric ATP binding and hydrolysis activity of the Thermus aquaticus MutS dimer is key to modulation of its interactions with mismatched DNA.</a> Biochemistry. 43 (41), 13115-13128 (2004).</li><li>Gradia, S., Acharya, S., Fishel, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+human+mismatch+recognition+complex+hMSH2-hMSH6+functions+as+a+novel+molecular+switch.">The human mismatch recognition complex hMSH2-hMSH6 functions as a novel molecular switch.</a> Cell. 91 (7), 995-1005 (1997).</li><li>Mazur, D. J., Mendillo, M. L., Kolodner, R. D., D, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Inhibition+of+Msh6+ATPase+activity+by+mispaired+DNA+induces+a+Msh2(ATP)-Msh6(ATP)+state+capable+of+hydrolysis-independent+movement+along+DNA.">Inhibition of Msh6 ATPase activity by mispaired DNA induces a Msh2(ATP)-Msh6(ATP) state capable of hydrolysis-independent movement along DNA.</a> Mol Cell. 22 (1), 39-49 (2006).</li></ol>

The example of a DNA mismatch binding protein described here illustrates the power and utility of transient kinetic methods for studying the mechanisms of biological molecules. Stopped-flow measurements on the single turnover time scale provided unambiguous evidence for rapid and specific binding of Msh2-Msh6 protein to a mismatched base pair and formation of a long-lived protein X DNA complex in the reaction 9. Moreover, stopped-flow (and quench-flow) analysis of ATPase activity provided direct evidence for M...

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">	
			<div>
			<table border="1">
 <tr>
 <td>DNA name</td>
 <td>Sequence</td>
 </tr>
 <tr>
 <td>37 G</td>
 <td>5'- ATT TCC TTC AGC AGA TAT G T A CCA TAC TGA TTC ACA T -3'</td>
 </tr>
 <tr>
 <td>37 T (2-Ap)</td>
 <td>5'- ATG TGA ATC AGT ATG GTA TApT ATC TGC TGA AGG AAA T -3'</td>
 </tr>
 <tr>
 <td>37 T</td>
 <td>5'- ATG TGA ATC AGT ATG GTA T A T ATC TGC TGA AGG AAA T -3'</td>
 </tr>
</table>		</div>

application of stopped-flow kinetics methods to investigate the mechanism of action of a dna repair protein

Transient kinetic analysis is indispensable for understanding the workings of biological macromolecules, since this approach yields mechanistic information including active site concentrations and intrinsic rate constants that govern macromolecular function. In case of enzymes, for example, transient or pre-steady state measurements identify and characterize individual events in the reaction pathway, whereas steady state measurements only yield overall catalytic efficiency and specificity. Individual events such as protein-protein or protein-ligand interactions and rate-limiting conformational changes often occur in the millisecond timescale, and can be measured directly by stopped-flow and chemical-quench flow methods. Given an optical signal such as fluorescence, stopped-flow serves as a powerful and accessible tool for monitoring reaction progress from substrate binding to product release and catalytic turnover1,2.
Here, we report application of stopped-flow kinetics to probe the mechanism of action of Msh2-Msh6, a eukaryotic DNA repair protein that recognizes base-pair mismatches and insertion/deletion loops in DNA and signals mismatch repair (MMR)3-5. In doing so, Msh2-Msh6 increases the accuracy of DNA replication by three orders of magnitude (error frequency decreases from ~10-6 to10-9 bases), and thus helps preserve genomic integrity. Not surprisingly, defective human Msh2-Msh6 function is associated with hereditary non-polyposis colon cancer and other sporadic cancers6-8. In order to understand the mechanism of action of this critical DNA metabolic protein, we are probing the dynamics of Msh2-Msh6 interaction with mismatched DNA as well as the ATPase activity that fuels its actions in MMR. DNA binding is measured by rapidly mixing Msh2-Msh6 with DNA containing a 2-aminopurine (2-Ap) fluorophore adjacent to a G:T mismatch and monitoring the resulting increase in 2-aminopurine fluorescence in real time. DNA dissociation is measured by mixing pre-formed Msh2-Msh6 G:T(2-Ap) mismatch complex with unlabeled trap DNA and monitoring decrease in fluorescence over time9. Pre-steady state ATPase kinetics are measured by the change in fluorescence of 7-diethylamino-3-((((2-maleimidyl)ethyl)amino)carbonyl) coumarin)-labeled Phosphate Binding Protein (MDCC-PBP) on binding phosphate (Pi) released by Msh2-Msh6 following ATP hydrolysis9,10.
The data reveal rapid binding of Msh2-Msh6 to a G:T mismatch and formation of a long-lived Msh2-Msh6 G:T complex, which in turn results in suppression of ATP hydrolysis and stabilization of the protein in an ATP-bound form. The reaction kinetics provide clear support for the hypothesis that ATP-bound Msh2-Msh6 signals DNA repair on binding a mismatched base pair in the double helix.
F. Noah Biro and Jie Zhai contributed to this paper equally.

Watch this Scientific Journal Video about Application of Stopped-flow Kinetics Methods to Investigate the Mechanism of Action of a DNA Repair Protein at JoVE.com

Application of Stopped-flow Kinetics Methods to Investigate the Mechanism of Action of a DNA Repair Protein

Msh2-Msh6 is responsible for initiating repair of replication errors in DNA. Here we present a transient kinetics approach towards understanding how this critical protein works. The report illustrates stopped-flow experiments for measuring the coupled DNA binding and ATPase kinetics underlying Msh2-Msh6 mechanism of action in DNA repair.

Transient kinetic analysis is indispensable for understanding the workings of biological macromolecules, since this approach yields mechanistic ...

Research

Education

JoVE Journal

JoVE Core

Biology

Genetics

DNA Structure and Function

SCIENTISTS IN ACTION

Genetic Studies of Human DNA Repair Proteins Using Yeast as a Model System 

Understanding the roles of human DNA repair proteins in genetic pathways is a formidable challenge to many researchers.  Genetic studies in mammalian ...

Imaging Mismatch Repair and Cellular Responses to DNA Damage in Bacillus subtilis

Imaging Mismatch Repair and Cellular Responses to DNA Damage in Bacillus subtilis

Both prokaryotes and eukaryotes respond to DNA damage through a complex set of physiological changes. Alterations in gene expression, the redistribution ...

The Importance of Correct Protein Concentration for Kinetics and Affinity Determination in Structure-function Analysis 

In this study, we explore the interaction between the bovine cysteine protease inhibitor cystatin B and a catalytically inactive form of papain (Fig. 1), ...

Application of an In vitro DNA Protection Assay to Visualize Stress Mediation Properties of the Dps Protein

Application of an In vitro DNA Protection Assay to Visualize Stress Mediation Properties of the Dps Protein

Oxidative stress is an unavoidable byproduct of  aerobic life.  Molecular oxygen is  essential for terrestrial metabolism, but it also takes part in many ...

Real-time Imaging of Single Engineered RNA Transcripts in Living Cells Using Ratiometric Bimolecular Beacons

The growing realization that both the temporal and spatial regulation of gene expression can have important consequences on cell function has led to the ...

Development of Inhibitors of Protein-protein Interactions through REPLACE: Application to the Design and Development Non-ATP Competitive CDK Inhibitors

REPLACE is a unique strategy developed to more effectively target protein-protein interactions (PPIs). It aims to expand available drug target space by ...

Chromatin Immunoprecipitation Assay for the Identification of Arabidopsis Protein-DNA Interactions In Vivo

Chromatin Immunoprecipitation Assay for the Identification of Arabidopsis Protein-DNA Interactions In Vivo

Intricate gene regulatory networks orchestrate biological processes and developmental transitions in plants. Selective transcriptional activation and ...

Amplification, Next-generation Sequencing, and Genomic DNA Mapping of Retroviral Integration Sites

Retroviruses exhibit signature integration preferences on both the local and global scales. Here, we present a detailed protocol for (1) generation of ...

Advanced Confocal Microscopy Techniques to Study Protein-protein Interactions and Kinetics at DNA Lesions

Local microirradiation with lasers represents a useful tool for studies of DNA-repair-related processes in live cells. Here, we describe a methodological ...

Methods to Study Changes in Inherent Protein Aggregation with Age in Caenorhabditis elegans

Methods to Study Changes in Inherent Protein Aggregation with Age in Caenorhabditis elegans

In the last decades, the prevalence of neurodegenerative disorders, such as Alzheimer's disease (AD) and Parkinson's disease (PD), has grown. These ...