Human BDNF Recombinant Protein. BDNF (Brain-Derived Neurotrophic Factor) 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, pro-BDNF is biologically active and is secreted in 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. Signaling occurs mainly through the tyrosine kinase receptor TrkB, although binding to the lower-affinity receptor, p75-NTR, has also been demonstrated. BDNF promotes neuronal survival and differentiation and has been shown to play a critical role in memory formation and s