Nidogen
Nidogens, formerly known as entactins, are a family of sulfated monomeric glycoproteins located in the basal lamina[1] of parahoxozoans.[2] Two nidogens have been identified in humans: nidogen-1 (NID1) and nidogen-2 (NID2).[3] Remarkably, vertebrates are still capable of stabilizing basement membrane in the absence of either identified nidogen.[4] In contrast, those lacking both nidogen-1 and nidogen-2 typically die prematurely during embryonic development as a result of defects existing in the heart and lungs.[5] Nidogen have been shown to play a crucial role during organogenesis in late embryonic development, particularly in cardiac and lung development.[6] From an evolutionary perspective, nidogens are highly conserved across vertebrates and invertebrates, retaining their ability to bind laminin.[7]
In nematodes, nidogen-1 is necessary for axon guidance, but not for basement membrane assembly.[8]