Nerve growth factor: structure and mechanism of action.

Abstract

This chapter presents the structure and mechanism of action of nerve growth factor (NGF). NGF has been purified to homogeneity from the submaxillary gland of the adult male mouse and from the venom of the cobra Naja naja . Both proteins are dimers of identical polypeptide chains which have a molecular weight of about 13,000. The chapter presents the primary structures of mouse and cobra NGF. The mouse NGF sequence is the continuous line, and the different residues that appear in the tentative Naja naja NGF sequence are indicated at their respective positions below the mouse sequence. The polypeptide chain of mouse NGF is 118 residues while that of cobra NGF is 117 residues. Three intramolecular disulfide bridges link half-cystinyl residues 15 to 80, 58 to 108, and 68 to 110 in the mouse protein and, as judged by the identical location of the half-cystinyl residues, in the Naja naja protein as well. The proteins from these two sources are quite similar in amino acid sequence, having identical amino acid residues in about 65% of the positions in their sequences.