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Single molecule analysis of DNA processes

The Tethered Particle Motion (TPM) technique allows to monitor the changes in DNA length by measuring the amplitude of movement of a bead attached to the free end of a DNA molecule immobilized by the other end on a glass slide. This technique has a high sensitivity and detects single protein binding to a DNA molecule causing bending or looping of the DNA tether. TPM is a tool of choice for analysing DNA-protein interactions and recombination processes (Pouget et al, NAR 2004; Dennis et al, Embo J 2004; Pouget et al, NAR 2006, Tardin, Manghi et al, Phys. Biol. 2010).

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TPM-on-a-chip (S. Chevalier, C. Tardin, L. Salomé – project supported by ANR Nano)

 

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XerCD-dif DNA recombination (C. Diagne and C. Tardin in collaboration with P. Rousseau, F. Cornet, LMGM, Toulouse)

 

DNA denaturation : formation and lifetime of bubbles (A. Brunet and C. Tardin in collaboration with N. Destainville, J. Palmeri, M. Manghi, LPT, Toulouse)

Single molecule experiments provide invaluable information which is not accessible by conventional methods based on average measurements. We believe that a larger community of academic research but also screening and diagnosis activities in pharmaceutical industry would benefit from such technologies provided they would reach high throughput capacity. In this context, we developed a ready-to-use tool combining functionalized supports and driving-acquisition-analysis software for the parallelization of DNA Tethered Particle Motion (TPM) measurements (French patent n°FR 1057031 - Plénat, Tardin et al, NAR 2012). Current work is dedicated to the optimization and full characterization of the technique.