MIFLATLPLFWIMISASRGGHWGAWMPSTISAFEGTCVSIPCRFDFPDELRPAVVHGVWYFNSPYPKNYPPVVFKSRTQVVHESFQGRSRLLGDLGLRNCTLLLSTLSPELGGKYYFRGDLGGYNQYTFSEHSVLDIVNTPNIVVPPEVVAGTEVEVSCMVPDNCPELRPELSWLGHEGLGEPTVLGRLREDEGTWVQVSLLHFVPTREANGHRLGCQAAFPNTTLQFEGYASLDVKYPPVIVEMNSSVEAIEGSHVSLLCGADSNPPPLLTWMRDGMVLREAVAKSLYLDLEEVTPGEDGVYACLAENAYGQDNRTVELSVMYAPWKPTVNGTVVAVEGETVSILCSTQSNPDPILTIFKEKQILATVIYESQLQLELPAVTPEDDGEYWCVAENQYGQRATAFNLSVEFAPIILLESHCAAARDTVQCLCVVKSNPEPSVAFELPSRNVTVNETEREFVYSERSGLLLTSILTIRGQAQAPPRVICTSRNLYGTQSLELPFQGAHRLMWAKIGPVGAVVAFAILIAIVCYITQTRRKKNVTESSSFSGGDNPHVLYSPEFRISGAPDKYESEKQRLGSERRLLGLRGESPELDLSYSHSDLGKRPTKDSYTLTEELAEYAEIRVK

Adhesion molecule that mediates interactions between myelinating cells and neurons by binding to neuronal sialic acid-containing gangliosides and to the glycoproteins RTN4R and RTN4RL2 (PubMed:7533044, PubMed:12089450, PubMed:27922006). Not required for initial myelination, but seems to play a role in the maintenance of normal axon myelination (PubMed:7516497, PubMed:9262180, PubMed:9482781, PubMed:9482783, PubMed:9469574, PubMed:10625334). Protects motoneurons against apoptosis, also after injury; protection against apoptosis is probably mediated via interaction with neuronal RTN4R and RTN4RL2 (PubMed:26335717). Required to prevent degeneration of myelinated axons in adults; this probably depends on binding to gangliosides on the axon cell membrane (PubMed:15953602, PubMed:19158290). Negative regulator of neurite outgrowth that inhibits axon longitudinal growth (PubMed:19158290, PubMed:27922006, PubMed:12089450). Negative regulator of neurite outgrowth; in dorsal root ganglion neurons the inhibition is mediated primarily via binding to neuronal RTN4R or RTN4RL2 and to a lesser degree via binding to neuronal gangliosides (PubMed:17640868). In cerebellar granule cells the inhibition is mediated via binding to neuronal gangliosides (PubMed:17640868). In sensory neurons, inhibition of neurite extension depends only partially on RTN4R, RTN4RL2 and gangliosides (By similarity). Inhibits axon outgrowth by binding to RTN4R (PubMed:12089450). Preferentially binds to alpha-2,3-linked sialic acid (PubMed:7533044, PubMed:27922006). Binds ganglioside Gt1b (PubMed:27922006).