Metal Cofactors in Natively Unstructured Proteins: Exploring Zn2+ Binding in Prothymosin Grant uri icon

abstract

  • Scant information is available at the molecular level describing the metal binding motifs in natively unfolded metalloproteins. The global fold adopted by these proteins in the halo state is unknown but essential for evaluation of the mechanisms of protein function. Of the few metal binding domains located in natively unfolded proteins most are unique. Elucidation of the molecular features and biophysical properties of these proteins with their metal cofactors will provide insight into their function and potentially novel mechanisms of action, thus contributing to a more complete understanding of biological chemistry. A specific research plan for the examination of Zn2+-binding in the natively unfolded, nuclear protein prothymosin-a is described. The function of this protein remains unclear, but prothymosin-a is predicted to play an essential role in the cell because of its high expression level,' wide distribution, and high sequence conservation across species. Since this protein is devoid of the amino acid residues commonly found in Zn2+ -binding proteins, the binding site or sites are sure to be unique. The experimental strategy developed for elucidating Zn2+ -binding in prothymosin-a is multifaceted, applying spectroscopy, chemical synthesis, and recombinant DNA methodology. This approach is necessary because this type of protein presents a problem to standard nuclear magnetic resonance (NMR) spectroscopy and X-ray crystallography protein structure solving methodology. However, magnetic resonance will still serve as a prime spectroscopic method in these studies, specifically one and two-dimensional NMR and electron paramagnetic resonance (EPR) spectroscopy.

date/time interval

  • July 2004 - August 2006