The function of Ensembl gene identifier ENSG00000040608 (RTN4R, reticulon 4 receptor) is as follows. Receptor for RTN4, OMG and MAG (PubMed:12037567, PubMed:12068310, PubMed:12089450, PubMed:12426574, PubMed:12839991, PubMed:16712417, PubMed:18411262, PubMed:19052207). Functions as a receptor for the sialylated gangliosides GT1b and GM1 (PubMed:18411262). Besides, functions as a receptor for chondroitin sulfate proteoglycans (By similarity). Can also bind heparin (By similarity). Intracellular signaling cascades are triggered via the coreceptor NGFR (PubMed:12426574). Signaling mediates activation of Rho and downstream reorganization of the actin cytoskeleton (PubMed:16712417, PubMed:22325200). Mediates axonal growth inhibition (PubMed:12839991, PubMed:19052207, PubMed:28892071). Plays a role in regulating axon regeneration and neuronal plasticity in the adult central nervous system. Plays a role in postnatal brain development. Required for normal axon migration across the brain midline and normal formation of the corpus callosum. Protects motoneurons against apoptosis; protection against apoptosis is probably mediated via interaction with MAG. Acts in conjunction with RTN4 and LINGO1 in regulating neuronal precursor cell motility during cortical development. Like other family members, plays a role in restricting the number dendritic spines and the number of synapses that are formed during brain development (PubMed:22325200). {ECO:0000250|UniProtKB:Q99PI8, ECO:0000269|PubMed:12037567, ECO:0000269|PubMed:12426574, ECO:0000269|PubMed:12839991, ECO:0000269|PubMed:14966521, ECO:0000269|PubMed:16712417, ECO:0000269|PubMed:18411262, ECO:0000269|PubMed:19052207, ECO:0000269|PubMed:28892071}. (Microbial infection) Acts as a receptor for Reovirus type 3. .