This motif is found in Diaphanous-related formins. It binds the N-terminal GTPase-binding domain; this link is broken when GTP-bound Rho binds to the GBD and activates the protein. The addition of DAD to mammalian cells induces actin filament formation, stabilises microtubules, and activates serum-response mediated transcription ([1]).

1: Disruption of the Diaphanous-Related Formin Drf1 Gene Encoding mDia1 Reveals a Role for Drf3 as an Effector for Cdc42. Peng J, Wallar BJ, Flanders A, Swiatek PJ, Alberts AS; Curr Biol 2003;13:534-545. PMID:12676083

2: Identification of a carboxyl-terminal diaphanous-related formin homology protein autoregulatory domain. Alberts AS; J Biol Chem 2001;276:2824-2830. PMID:11035012