Involved in neural development, regulating the establishment of proper connectivity within the nervous system. Plays a role in the establishment of the anterior-posterior axis during gastrulation. Regulates the differentiation and cellular process formation of oligodendrocytes and myelination of small-diameter axons in the central nervous system (CNS) (PubMed:26188006). Promotes activation of focal adhesion kinase. May function as a cellular signal transducer (By similarity). Homodimer; disulfide-linked (Probable). May also form heterodimer with either TENM1 or TENM2 or TENM3 (By similarity). EGF-like domains 2 and 5 which have an odd number of cysteines might enable the formation of intermolecular disulfide bonds. Cytoplasmic proline-rich regions could serve as docking domains for intracellular SH3-containing proteins. The disease is caused by variants affecting the gene represented in this entry. Belongs to the tenascin family. Teneurin subfamily. Truncated N-terminus.