THE STRUCTURE OF GABP-ALPHA BETA - AN ETS DOMAIN ANKYRIN REPEAT HETERODIMER BOUND TO DNA/

GA-binding protein (GABP) is a transcriptional regulator composed of t wo structurally dissimilar subunits. The alpha subunit contains a DNA- binding domain that is a member of the ETS family, whereas the beta su bunit contains a series of ankyrin repeats. The crystal structure of a ternary complex containing a GABP alpha/beta ETS domain-ankyrin repea t heterodimer bound to DNA was determined at 2.15 angstrom resolution. The structure shows how an ETS domain protein can recruit a partner p rotein using both the ETS domain and a carboxyl-terminal extension and provides a view of an,extensive protein-protein interface formed by a set of ankyrin repeats. The structure also reveals how the GABP alpha ETS domain binds to its core GGA DNA-recognition motif.