The heterodimer formed by NGFR and SORCS2 functions as receptor for the precursor forms of NGF (proNGF) and BDNF (proBDNF) (PubMed:22155786, PubMed:24908487). ProNGF and proBDNF binding both promote axon growth cone collapse (in vitro) (PubMed:22155786, PubMed:24908487). Plays a role in the regulation of dendritic spine density in hippocampus neurons (By similarity). Required for normal neurite branching and extension in response to BDNF (PubMed:27457814). Plays a role in BDNF-dependent hippocampal synaptic plasticity. Together with NGFR and NTRK2, is required both for BDNF-mediated synaptic long-term depression and long-term potentiation (PubMed:27457814). ProNGF binding promotes dissociation of TRIO from the heterodimer, which leads to inactivation of RAC1 and/or RAC2 and subsequent reorganization of the actin cytoskeleton (PubMed:22155786). Together with the retromer complex subunit VPS35, required for normal expression of GRIN2A at synapses and dendritic cell membranes. Required for normal expression of the amino acid transporter SLC1A1 at the cell membrane, and thereby contributes to protect cells against oxidative stress (By similarity). Does not promote Schwann cell apoptosis in response to proBDNF. SorCS2 104 kDa chain and SorCS2 18 kDa chain together promote Schwann cell apoptosis in response to proBDNF. Homodimer (in vitro) (By similarity). Heterodimer with NGFR. The extracellular domains of the heterodimer bind the precursor form of NGF (proNGF) (PubMed:22155786, PubMed:24908487). Has much higher affinity for proNGF than for mature NGF (PubMed:24908487). Can also bind mature NGF and BDNF (By similarity). Each chain in the receptor dimer interacts (via extracellular domain) with an NGF dimer (in vitro) (By similarity). Interacts with the precursor forms of BDNF (proBDNF) and NTF3 (proNT3) (PubMed:24908487). The cytoplasmic region of the heterodimer formed by NGFR and SORCS2 binds TRIO. ProNGF binding mediates dissociation of TRIO from the receptor complex (PubMed:22155786). Interacts with SLC1A1. Interacts with VPS35. Interacts (via extracellular domain) with NTRK2 (via extracellular domain). Interacts with VPS35. Interacts (via extracellular domain) with GRIN2A (By similarity). Detected on neurons in the caudate region (PubMed:28469074). Detected on neurons in the hippocampus (at protein level) (PubMed:30840898). Highly expressed in brain and kidney. Detected at low levels in heart, liver, small intestine, skeletal muscle and thymus (PubMed:11499680). Proteolytic cleavage removes a propeptide, giving rise to a 122 kDa chain that includes a cytoplasmic tail. Further cleavage gives rise to a 104 kDa chain that lacks the cytoplasmic tail, and a membrane-bound 18 kDa chain. The 104 kDa chain remains bound to the 18 kDa chain. N-glycosylated. Expression is decreased in the brains of Huntington disease (HD) patients after the onset of symptoms. Belongs to the VPS10-related sortilin family. SORCS subfamily. The N-terminus of the protein was constructed in analogy to that of the mouse ortholog using the sequence of chromosome 4.