Lighting up individual DNA binding proteins with quantum dots.
The ability to determine the precise loci and occupancy of DNA-binding proteins is instrumental to our understanding of cellular processes like gene expression and regulation. We propose a single-molecule approach for the direct visualization of proteins bound to their template DNA. Fluorescent quantum dots (QD) are used to label proteins bound to DNA, allowing multicolor, nanometer-resolution localization. Protein-DNA complexes are linearly extended and imaged to determine the precise location of the protein binding sites. The method is demonstrated by detecting individual QD-labeled T7-RNA polymerases on the T7 bacteriophage genome. This work demonstrates the potential of this approach to precisely read protein binding position or, alternatively, "write" such information on extended DNA with QDs via sequence-specific molecular recognition.
Ebenstein
Yuval
Y
Department of Chemistry and Biochemistry, DOE Institute for Genomics and Proteomics, UCLA, Los Angeles, California 90095, USA. uv@chem.ucla.edu
Gassman
Natalie
N
Kim
Soohong
S
Antelman
Josh
J
Kim
Younggyu
Y
Ho
Sam
S
Samuel
Robin
R
Michalet
Xavier
X
Weiss
Shimon
S
D004247:DNA / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D005453:Fluorescence; D045663:Quantum Dots; D014764:Viral Proteins / Q000378:metabolism
D004268:DNA-Binding Proteins; D014764:Viral Proteins; D004247:DNA; C062210:bacteriophage T7 RNA polymerase; D012321:DNA-Directed RNA Polymerases