Michael G. Fried, Ph.D. 

A.B. (Biology) Dartmouth College, 1976
Ph.D. (Molecular Biophysics) Yale University, 1982
Postdoctoral (Biochemistry) University of Minnesota, 1982-85
Email: Michael.fried@uky.edu
Telephone:  859-323-1205

 Research Interests  |  Publications  |  PubMed

Research Interests

Protein-DNA and Protein-Protein Interactions 

The assembly of macromolecular complexes is an essential step in many cellular processes. We are interested in the mechanisms that govern the assembly rates and the equilibrium stabilities of such complexes.  We are currently exploring these issues for selected protein-DNA and protein-protein interactions.

 1.         Assembly of protein-DNA complexes.  Protein-DNA complexes play central roles in many of the transactions in which DNA is involved, including transcription, DNA replication, and chromosomal DNA packaging.  We wish to understand the roles of DNA bending, protein-protein interactions and macromolecular solvation in the formation of protein-DNA complexes.  The molecular systems currently under investigation include: The human O6-alkylguanine-DNA alkyltransferase (AGT), and human and yeast TATA-binding proteins (TBP).

Above: a model of the human AGT protein associated with DNA.  Source: Wibley, J.E., et al. (1995) Anti-Cancer Drug Design. 10, 75.  While this model depicts isolated binding, our binding data indicate that AGT-DNA interactions are highly cooperative.

Above: a 1.9 Å resolution structure of Arabidopsis Thaliana TBP associated with DNA.  Source: J.L.Kim & S.K.Burley (1994) Nat. Struct. Biol. 1, 638.  The extensive protein-protein contacts differ significantly from those found in the crystal structure of this TBP in the absence of DNA 

2.         Protein interactions that regulate blood-clot stability.  Many plasma proteins associate with the fibrin network that forms the scaffold of blood clots.  Among these are factor XIII, which stabilizes clots by catalyzing the formation of covalent crosslinks between fibrin monomers, and plasminogen, the precursor of the protease that cleaves fibrin during clot lysis. We are currently studying the binding of these proteins to fibrin and its precursor, fibrinogen, with the goal of learning how these assemblies determine clot structure and stability.  

Above: secondary structure diagram of the D-dimer complex of fibrin. The individual chains are color coded. The dimer interface essential for clot formation is shown at center. Source: S.J.Everse et al. (1998) Biochemistry 37 8637. 

Representative Publications 

Effects of Zinc Occupancy on Human O⁶ -Alkylguanine-DNA Alkyltransferase.  J.J. Rasimas, S. Kanugula, P.M. Dalessio, I.J. Ropson, M.G. Fried and A.E. Pegg. Biochemistry 42, 980-990 (2003). 

Interaction of O⁶-Alkylguanine DNA Alkyltransferase with DNA: Effects of Protein- and DNA-Alkylation.  J. J. Rasimas, A. E. Pegg and M.G. Fried. J. Biol. Chem. 278, 7973-7980 (2003). 

Active-Site Alkylation Destabilizes Human O⁶-Alkylguanine DNA Alkyltransferase. J.J. Rasimas, P. Dalessio, I. Ropson, A.E. Pegg and M.G. Fried. Protein Science 13, 301-305 (2004). 

Self-Association of the N-Terminal Domain of the Yeast TATA-Binding Protein (TBP).  C. Adams, S. Kar, J.E. Hopper and M.G. Fried. J. Biol. Chem. 279, 1376-1382 (2004). 

Interactions and Reactions of Ferritin with DNA.  N. Sugurladze, K. Thompson, J. Beard, J. Connor, M.G. Fried. J. Biol. Chem. 279, 14694-14702 (2004). 

ATP Effects On Insulin Degrading Enzyme Are Mediated Primarily Through Its Triphosphate Moiety. E.S. Song, M.A. Juliano, L. Juliano, M.G. Fried, S.L. Wagner and L.B. Hersh J. Biol. Chem. 279, 54216-54220 (2004). 

Characterization of Nuclear Ferritin and Mechanism of Translocation. N. Surguladze, S. Patton, A. Cozzi, M. G. Fried and J. R. Connor.  Biochem. J. 388, 731-740 (2005). 

Mutation Of Active Site Residues Of Insulin Degrading Enzyme Alters Allosteric Interactions. E.S. Song, A.Daily, M.G. Fried, M.A. Juliano, L. Juliano and L.B. Hersh.  J. Biol. Chem. 280, 17701-17706 (2005). 

Cation Binding Linked To A Sequence-Specific CAP-DNA Interaction.  D. F. Stickle and M.G. Fried.  Biophys. Chem. (2006) in press. 

Protein-DNA Interactions at Sedimentation Equilibrium.  M.A. Daugherty and M. G. Fried in: Modern Analytical Ultracentrifugation: Techniques and Method, D. Scott, Ed., Royal Society of Chemistry, Oxford (2005) pp 195-209. 

Analysis Of Protein-DNA Equilibria By Native Gel Electrophoresis. C.A. Adams and M.G. Fried, in Protein Interactions: Biophysical Approaches for the Study of Multi-Component Systems. P. Schuck, Ed., Academic Press, NY (2006) in press.