This domain is found in a group of sequences from eukaryotic parasites, including Toxofilin from Toxoplasma gondii, an actin-binding protein involved in invasion. This domain interacts with the host mammalian actin. It folds into five helices connected by loops [1].

1: Toxofilin from Toxoplasma gondii forms a ternary complex with an antiparallel actin dimer. Lee SH, Hayes DB, Rebowski G, Tardieux I, Dominguez R; Proc Natl Acad Sci U S A. 2007;104:16122-16127. PMID:17911258