�� An Overview of Protein-DNA and Protein-RNA Interactions

Department of Chemistry-Biology, University of Qu�bec at Trois-Rivi�res,C.P. 500, TR (Qu�bec) Canada G9A 5H7H.A.

Tajmir-Riahi

In this review the fundamental question of how does protein-DNA or protein-RNA interactions affect the structures and dynamics of DNA, RNA, and protein is addressed. Two models of human serum albumin (HSA) bindings to calf-thymus DNA and transfer RNA (tRNA) are presented here. In these models the binding sites, stability and structural aspects of DNA-protein and RNA-protein are discussed. Electrostatic binding of DNA or RNA via backbone phosphate group to the positively�charged amino acids on the surface of protein is prevailing. Two binding sites with K₁ = 4.8 � 10⁵ M^-1 and K₂ = 6.1 � 10⁴ M^-1 for protein-DNA and one binding affinity with K = 1.45 � 10⁴ M^-1 for protein-RNA are observed. A partial B to A-DNA transition is observed for protein-DNA complexes, while tRNA remains in A-family structure upon protein interaction.

Keywords:

DNA, Protein, Binding mode, Binding constant, Secondary structure capillary electrophoresis, FTIR spectroscopy�