Single Molecule Studies of DNA Dynamics (2008)

Undergraduates: Maxwell Ballenger, Jay K. Fisher, Kerry Bloom Jay K. Fisher Kerry Bloom, E. Tim O'Brien (these are faculty, but not my primary advisor...)

Faculty Advisor: Rich Superfine
Department: Physics & Astronomy

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The progress of scientific understanding of the biochemical processes responsible for the cell's activities over the past century and a half has been incredible. Until advances in microscopy over the last decade, however, physical studies were rarely attempted. Existing methods for dynamical investigations inside the cell, such as Stokes' Law or microprobe insertion, are systematically inaccurate or irrelevant in the intracellular environment.

Forces during cell division may have an effect on later activities of the cell, such as the preferential transcription of certain parts of the genome. An accurate method for intracellular force measurement is necessary to further investigate their effect.

Using polymer relaxation dynamics, we have developed a method for force measurement from the perspective of a strand of chromatin. Our method has been used in vivo to calculate a late anaphase microtubule tension of 0.3 pN and is currently being tested in vitro to confirm its accuracy.