May play a role in anteroposterior axis elongation. In the embryo, expressed in early mesodermal cells, the neuroepithelial layer of the brain and the trunk neural tube, the neural layer of the retina and in the epithelial somite and dermomyotome. From mid-gastrulation to early somite stages, restricted to the posterior embryonic region but this posterior restriction is progressively lost during somitogenesis. As development proceeds, further restricted to the dorsal parts of the spinal cord and somites. In parallel, expression progresses caudally during axis elongation. Highest expression is found in E1-E3 embryos with a significant decrease after E3.5. Belongs to the immunoglobulin superfamily. DCC family.