Nidogen-1/Entactin: Proteins and Enzymes

Nidogen-2 (also called entactin-2) is a 200 kDa, secreted, basement membrane glycoprotein. Nidogens-1 and -2 are expressed in nearly all basement membranes where they interact with laminins, collagen type IV, and proteoglycan family members. Nidogen-2 contains three globular domains (G1-3) separated by a link region and an extended rod-shaped segment. The G1 domain is reported to bind type IV collagen, the G2 domain interacts with perlecan, and C-terminal G3 is associated with laminin binding. There is one EGF-like motif and a short peptide that ligates alpha 3 beta 1 integrins. The rod-shaped segment contains four additional EGF-like motifs and two thyroglobulin type 1 domains that serve as a binding site for alpha V beta 3 integrins.