Cell Adhesion Molecule 3 (CADM3)

IGSF4B is a brain-specific protein related to the calcium-independent cell-cell adhesion molecules known as nectins.The predicted 398-amino acid TSLL1 protein has an extracellular domain, a transmembrane domain, and a short cytoplasmic domain. The extracellular domain contains 3 Ig-like, C2-type loops with several potential N-glycosylation sites. NECL1 showed calcium-independent homophilic cell-cell adhesion activity. Furthermore, it showed calcium-independent heterophilic cell-cell adhesion activity with NECL2 (IGSF4), nectin-1 (PVRL1), or nectin-3 (PVRL3), but not with NECL5 (PVR) or nectin-2 (PVRL2). Yeast 2-hybrid analysis indicated that the PDZ domain-binding motif of NECL1 bound to the L27 domain-containing proteins DLG3, PALS2 (MPP6), and CASK, but unlike most other nectins.