This family includes the C-terminal domain of Dictyostelium discoideum Calcium-dependent cell adhesion molecule 1 (Swiss:P54657), which has an immunoglobulin-like fold. It tethers the protein to the cell membrane [1].

1: Solution structures of the adhesion molecule DdCAD-1 reveal new insights into Ca(2+)-dependent cell-cell adhesion. Lin Z, Sriskanthadevan S, Huang H, Siu CH, Yang D; Nat Struct Mol Biol. 2006;13:1016-1022. PMID:17057715