InterPro domain: IPR027817

This domain is found both alone (in the costars family of proteins) and at the C terminus of actin-binding Rho-activating protein (ABRA). It binds to actin, and in muscle regulates the actin cytoskeleton and cell motility [ 1 , 2 ]. It has a winged helix-like fold consisting of three alpha-helices and four antiparallel beta strands. Unlike typical winged helix proteins it does not bind to DNA, but contains a hydrophobic groove which may be responsible for interaction with other proteins [ 3 ].

1. STARS, a striated muscle activator of Rho signaling and serum response factor-dependent transcription. J. Biol. Chem. 277, 24453-9
2. Costars, a Dictyostelium protein similar to the C-terminal domain of STARS, regulates the actin cytoskeleton and motility. J. Cell. Sci. 123, 3745-55
3. Solution structure of the human HSPC280 protein. Protein Sci. 20, 216-23