Nerve growth factor (NGF) is a dimer of 118-residue polypeptide chains linked non-covalently. Both these polypeptides contain three intramolecular disulphide bridges. It forms the prototype of the neurotrophin growth factor family. In male mouse submandibular salivary gland, NGF is present in high amounts, and is present as a high molecular weight complex called nerve growth factor-7S (NGF-7S). NGF-7S is an α2β2γ2 complex, where β2-NGF is the active neurotrophin, and is linked to the dimers of the glandular kallikrein serine proteinases members, α-NGF and γ-NGF.
Nerve growth factor (NGF) is a neurotrophin, which facilitates the differentiation and survival of specific subtypes of neurons of central nervous system and peripheral nervous system. However, nerve growth factor-7S (NGF-7S) lacks any neurotrophic activity as most part of β-NGF subunit is buried within the NGF-7S complex.
