NT3TrkC

NT3TrkC, also known as the TrkC receptor or neurotrophin-3 receptor, refers to the receptor tyrosine kinase TrkC encoded by the NTRK3 gene in humans. It is the high-affinity receptor for the neurotrophin-3 (NT-3) ligand and is part of the Trk receptor family, which also includes TrkA and TrkB.

The TrkC protein has an extracellular ligand-binding domain, a single transmembrane segment, and an intracellular tyrosine kinase domain. Binding of NT-3 induces receptor dimerization and autophosphorylation, activating downstream signaling cascades such as PI3K-Akt, Ras-MAPK, and PLCγ pathways. These signals promote neuronal survival, differentiation, axon and dendrite growth, and synaptic plasticity. The TrkC receptor can cooperate with the p75 neurotrophin receptor to modulate cellular responses and sensitivity to neurotrophins.

Expression of TrkC is developmentally regulated and is detected in various populations of neurons in both the peripheral and central nervous systems. It plays a crucial role in the development and maintenance of certain proprioceptive and sensory neurons and contributes to the formation and refinement of neural circuits.

Clinical significance includes two main areas. In cancer biology, rearrangements of NTRK3 can produce constitutively active fusion proteins that drive tumor growth in several cancers; TRK inhibitors that target these fusions, such as larotrectinib and entrectinib, are approved treatments for NTRK fusion–positive tumors. In neuroscience, dysregulation of NT-3/TrkC signaling has been explored in relation to neurodevelopmental disorders, though evidence remains to be clarified.

NT3TrkC is also referred to as TrkC, neurotrophic receptor tyrosine kinase 3, or NTRK3.