PMID: 10535945 , Related PDB id: 1QGP

Authors:

Schade M, Turner CJ, Kuhne R, Schmieder P, Lowenhaupt K, Herbert A, Rich A, Oschkinat H

Title:

The solution structure of the Zalpha domain of the human RNA editing enzyme ADAR1 reveals a prepositioned binding surface for Z-DNA.

Journal:

Proc Natl Acad Sci U S A. 1999 Oct 26;96(22):12465-70.

Abstract:

Double-stranded RNA deaminase I (ADAR1) contains the Z-DNA binding domain Zalpha. Here we report the solution structure of free Zalpha and map the interaction surface with Z-DNA, confirming roles previously assigned to residues by mutagenesis. Comparison with the crystal structure of the (Zalpha)(2)/Z-DNA complex shows that most Z-DNA contacting residues in free Zalpha are prepositioned to bind Z-DNA, thus minimizing the entropic cost of binding. Comparison with homologous (alpha+beta)helix-turn-helix/B-DNA complexes suggests that binding of Zalpha to B-DNA is disfavored by steric hindrance, but does not eliminate the possibility that related domains may bind to both B- and Z-DNA.