Nerve growth factor
Nerve growth factor (NGF) is a neurotrophic factor and neuropeptide primarily involved in the regulation of growth, maintenance, proliferation, and survival of certain target neurons. It is perhaps the prototypical growth factor, in that it was one of the first to be described. Since it was first isolated by Nobel Laureates Rita Levi-Montalcini and Stanley Cohen in 1956, numerous biological processes involving NGF have been identified, two of them being the survival of pancreatic beta cells and the regulation of the immune system.
Structure[edit]
NGF is initially in a 7S, 130-kDa complex of 3 proteins – Alpha-NGF, Beta-NGF, and Gamma-NGF (2:1:2 ratio) when expressed. This form of NGF is also referred to as proNGF (NGF precursor). The gamma subunit of this complex acts as a serine protease, and cleaves the N-terminal of the beta subunit, thereby activating the protein into functional NGF.
The term nerve growth factor usually refers to the 2.5S, 26-kDa beta subunit of the protein, the only component of the 7S NGF complex that is biologically active (i.e. acting as a signaling molecule).
Interactions[edit]
Nerve growth factor has been shown to interact with Tropomyosin receptor kinase A.[26]
Clinical Use[edit]
NGF, specifically mouse (murine) nerve growth factor, has been available as a licensed medicine in China since 2003.[27] There is evidence of improved patient outcomes for several diseases of the nervous system, including acute intracerebral hemorrhage,[28] global developmental delay,[29] optic atrophy,[30] epilepsy [31] and cerebral palsy.[32] This is significant as there are few medicines which can treat injuries and diseases of the nervous system. Research and clinical use outside of China is limited despite a large body of evidence supporting its use.