ATP alters the diffusion mechanics of MutS on mismatched DNA.
The mismatch repair (MMR) initiation protein MutS forms at least two types of sliding clamps on DNA: a transient mismatch searching clamp (∼1 s) and an unusually stable (∼600 s) ATP-bound clamp that recruits downstream MMR components. Remarkably, direct visualization of single MutS particles on mismatched DNA has not been reported. We have combined real-time particle tracking with fluorescence resonance energy transfer (FRET) to image MutS diffusion dynamics on DNA containing a single mismatch. We show searching MutS rotates during diffusion independent of ionic strength or flow rate, suggesting continuous contact with the DNA backbone. In contrast, ATP-bound MutS clamps that are visually and successively released from the mismatch spin freely around the DNA, and their diffusion is affected by ionic strength and flow rate. These observations show that ATP binding alters the MutS diffusion mechanics on DNA, which has a number of implications for the mechanism of MMR.
Department of Physics, Bioengineering Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Korea.
Won-Ki
WK
Cho
Department of Physics, Bioengineering Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Korea.
Cherlhyun
C
Jeong
Department of Physics, Bioengineering Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Korea.
Daehyung
D
Kim
Department of Physics, Bioengineering Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Korea.
Minhyeok
M
Chang
Department of Chemistry, Bioengineering Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Korea.
Kyung-Mi
KM
Song
Department of Molecular Virology, Immunology and Medical Genetics The Ohio State University, Columbus, OH 43210, USA.
Jeungphill
J
Hanne
Department of Chemistry, Bioengineering Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Korea.
Changill
C
Ban
Department of Molecular Virology, Immunology and Medical Genetics The Ohio State University, Columbus, OH 43210, USA.|Physics Department, The Ohio State University, Columbus, OH 43210, USA.
Richard
R
Fishel
Department of Physics, Bioengineering Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Korea.|School of Interdisciplinary Bioscience and Bioengineering Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Korea.
Jong-Bong
JB
Lee
D000255:Adenosine Triphosphate / Q000737:chemistry* / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D020137:Base Pair Mismatch; D004247:DNA / Q000737:chemistry* / Q000378:metabolism; D053843:DNA Mismatch Repair; D004058:Diffusion; D019281:Dimerization; D005454:Fluorescence Polarization; D031541:Fluorescence Resonance Energy Transfer; D005456:Fluorescent Dyes; D007700:Kinetics; D051719:MutS DNA Mismatch-Binding Protein / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013824:Thermus / Q000737:chemistry* / Q000201:enzymology / Q000235:genetics
D001426:Bacterial Proteins; D005456:Fluorescent Dyes; D011994:Recombinant Proteins; D000255:Adenosine Triphosphate; D004247:DNA; D051719:MutS DNA Mismatch-Binding Protein