Mechanism of corepressor-mediated specific DNA binding by the purine repressor.

Journal Article (Journal Article)

The modulation of the affinity of DNA-binding proteins by small molecule effectors for cognate DNA sites is common to both prokaryotes and eukaryotes. However, the mechanisms by which effector binding to one domain affects DNA binding by a distal domain are poorly understood structurally. In initial studies to provide insight into the mechanism of effector-modulated DNA binding of the lactose repressor family, we determined the crystal structure of the purine repressor bound to a corepressor and purF operator. To extend our understanding, we have determined the structure of the corepressor-free corepressor-binding domain of the purine repressor at 2.2 A resolution. In the unliganded state, structural changes in the corepressor-binding pocket cause each subunit to rotate open by as much as 23 degrees, the consequences of which are the disengagement of the minor groove-binding hinge helices and repressor-DNA dissociation.

Full Text

Duke Authors

Cited Authors

  • Schumacher, MA; Choi, KY; Lu, F; Zalkin, H; Brennan, RG

Published Date

  • October 6, 1995

Published In

Volume / Issue

  • 83 / 1

Start / End Page

  • 147 - 155

PubMed ID

  • 7553867

International Standard Serial Number (ISSN)

  • 0092-8674

Digital Object Identifier (DOI)

  • 10.1016/0092-8674(95)90243-0


  • eng

Conference Location

  • United States