This is the C-terminal domain of Staufen proteins. It consists of an N-terminal Staufen-swapping motif (SSM) comprising two alpha helices, connected by a linker region to a dsRNA-binding-like domain ('RBD'). The 'RBD' has the fold of a functional dsRNA-binding domain, but lacks the residues required to bind RNA. This domain is responsible for dimerisation, the SSM from one molecule interacts with the 'RBD' of another [1].

1: Staufen1 dimerizes through a conserved motif and a degenerate dsRNA-binding domain to promote mRNA decay. Gleghorn ML, Gong C, Kielkopf CL, Maquat LE; Nat Struct Mol Biol. 2013;20:515-524. PMID:23524536