BDNF is a member of the NGF family of neurotrophic growth factors. Like other members of this family, BDNF supports neuron proliferation and survival. BDNF can bind to a low affinity cell surface receptor called LNGFR, which also binds other neurotrophins such as NGF, NT-3 and NT-4. However, BDNF mediates its neurotrophic properties by signaling through a high affinity cell surface receptor called gp145/trkB. BDNF is expressed as the C-terminal portion of a 247 amino acid polypeptide precursor, which also contains a signal sequence of 18 amino acid residue and a propeptide of 110 amino acid residues. Recombinant human BDNF is a 27.0 kDa homodimer of two 120 amino acid subunits linked by strong non-covalent interactions. Human and Mouse BDNF sequences are identical.