The ELK1 protein is comprised of several domains; the A domain is required for binding ELK1 to DNA, and the B domain allows ELK1 to bind to a dimer of its cofactor, serum response factor.
As depicted in Figure 1, the Elk1 protein is composed of several domains. Localized in the N-terminal region, the A domain is required for the binding of Elk1 to DNA. The B domain allows Elk1 to bind to a dimer of its cofactor, serum response factor (SRF). 
