Neurosecretory protein VGF is specifically expressed in a subpopulation of neuroendocrine cells, and is upregulated by nerve growth factor. Human VGF precursor is 615 amino acids (aa) in length. It contains an 22 aa signal sequence plus a 593 aa mature region. The structural organization of this gene is similar to that of the rat gene, and both the translated and the untranslated regions show a high degree of sequence similarity to the rat gene. The encoded secretory protein also shares similarities with the secretogranin/chromogranin family, however, its exact function is not known. Besides,VGF can affect the downstream signal transduction process of BDNF through its derived peptides, and affect the biological effects mediated by BDNF, such as neurodevelopment and synaptic plasticity., thus a binding ELISA assay was conducted to detect the interaction of recombinant human VGF and recombinant human BDNF. Briefly,biotin-linked VGF were diluted serially in PBS, with 0.01% BSA (pH 7.4). Duplicate samples of 100μl were then transferred to BDNF-coated microtiter wells and incubated for 1h at 37℃. Wells were washed with PBST 3 times and incubation with Streptavidin-HRP for 30min, then wells were aspirated and washed 5 times. With the addition of substrate solution, wells were incubated 15-25 minutes at 37℃. Finally, add 50µl stop solution to the wells and read at 450nm immediately. The binding activity of VGF and BDNF was shown in Figure 1, the EC50 for this effect is 0.066ug/mL.