Trk Receptor

Trk receptors are a family of three receptor tyrosine kinases (TrkA, TrkB, and TrkC), each of which can be activated by one or more of four neurotrophins-nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophins 3 and 4 (NT3 and NT4).

TrkA, TrkB, and TrkC are transmembrane proteins that comprise the TRK receptor family. These receptor tyrosine kinases are expressed in human neuronal tissue, and play an essential role in both the physiology of development and function of the nervous system through activation by neurotrophins (NTs). The latter are specific ligands known as NGF for TrkA, BDGF, and NT-4/5 for TrkB and NT3 for TrkC, respectively.

The binding of the ligand to the receptor triggers the oligomerisation of the receptors and phosphorylation of specific tyrosine residues in the intracytoplasmic kinase domain. This event results into the activation of signal transduction pathways leading to proliferation, differentiation and survival in normal and neoplastic neuronal cells.