Tropomyosin receptor kinase A–p75 neurotrophin receptor complex (TrkA–p75NTR complex)

The Tropomyosin receptor kinase A–p75 neurotrophin receptor (TrkA–p75NTR) complex is a high-affinity heteromeric signaling unit essential for mediating the biological effects of nerve growth factor (NGF) (PMID: 10433263). While TrkA is a receptor tyrosine kinase that can bind NGF independently, its association with the p75 neurotrophin receptor (p75NTR), a member of the TNF receptor superfamily, significantly increases the binding affinity and selectivity for NGF over other neurotrophins (UniProt P04629, P08138). This complex formation enhances the activation of pro-survival signaling pathways, including the PI3K/Akt and MAPK/ERK cascades, which are critical for the development and maintenance of the peripheral nervous system (PMID: 15121877). In pathological contexts, dysregulation of this complex is linked to oncogenesis, particularly in NTRK-fusion-positive cancers and neuroblastoma, as well as the sensitization of nociceptors in chronic pain conditions (PubMed: 29166321). Therapeutic interventions include small-molecule inhibitors like larotrectinib that target the kinase activity of TrkA and monoclonal antibodies like tanezumab that prevent NGF from binding to the complex (NIH: NCT00830180). Understanding the interplay between these two receptors is vital for developing targeted therapies that can selectively modulate neuronal survival or death signals.

Other names

NGF high-affinity receptor complexNTRK1–NGFR complexTrkA–p75 complexNerve growth factor high-affinity receptor

Tyrosine kinase inhibition (TrkA component), Ligand sequestration (anti-NGF antibodies), Competitive binding, Allosteric modulation