SCIENCE AT THE EDGE SEMINAR
http://www.pa.msu.edu/seminars/edge

Friday, October 11 at 11:30am

Room 1400 Biomedical and Physical Sciences Bldg.

Refreshments at 11:15 a.m.


Speaker: Wilma  Olson
         Director, Center for Molecular Biophysics & Biophysical Chemistry
         Rutgers University, New Jersey

Title:   DNA Mechanics and Gene Regulation

Abstract:

The binding of proteins or drugs to their DNA targets elicits a unique
conformational response in the double helix that is tied to the function and
activity of the associated ligands, e.g., transcriptional regulation, DNA
processing, DNA packaging.  In addition to the direct recognition elements
embedded in the linear sequence of bases (i.e., hydrogen bonding sites),
these molecular agents seemingly sense and/or induce an "indirect"
conformational response in the DNA base pairs that facilitates close
intermolecular fitting.  The observed responses of DNA to proteins and drugs
in high resolution crystal complexes reveal a code of intrinsic structure
and deformability built into the base sequence with implications for DNA
control at both local and higher-order levels of organization.  For example,
the bending of DNA associated with repeated sequence motifs helps to
organize the three-dimensional structure of longer fragments and to guide
the response of closed loops formed by the binding of proteins at distant
sites along the DNA to super helical stress.