TrkB

TrkB, encoded by the NTRK2 gene, is the receptor tyrosine kinase for brain-derived neurotrophic factor (BDNF) and neurotrophin-4/5. It is broadly expressed in the central nervous system, where BDNF/TrkB signaling strengthens synaptic plasticity, dendritic growth, and long-term potentiation, processes central to learning and memory. In the hypothalamus the same receptor participates in the regulation of appetite and body weight. TrkB signaling through SHC, PLC-gamma, and PI3K cascades also supports neuronal survival, and altered TrkB signaling has been linked to depression and to the response to antidepressant treatment, while oncogenic NTRK2 fusions occur in a subset of tumors.