Description: Brain derived neurotrophic factor (BDNF) is a member of the neurotrophin family. BDNF is synthesized as pre-proBDNF, followed by cleavage to proBDNF. Although further processing generates the mature, 14 kDa protein, proBDNF is biologically active and is secreted from synaptic vesicles along with the mature form. BDNF is widely expressed in the central nervous system, and acts in an autocrine and paracrine manner on several classes of neurons. BDNF promotes neuronal survival and differentiation, and has been shown to play a critical role in memory formation and synaptic regulation. Signaling occurs mainly through the tyrosine kinase receptor TrkB, although binding to the lower-affinity receptor p75NTR has also been demonstrated.