Nerve growth factor (NGF) is a protein that plays a crucial role in the growth, maintenance, and survival of neurons, which are the cells responsible for transmitting signals in the nervous system. It is essential for the development of the nervous system and helps in the repair of damaged neurons. NGF is produced by various cells in the body, including neurons and glial cells. NGF binds to specific receptors on the surface of neurons, triggering a series of cellular responses that promote cell growth and differentiation. This protein is particularly important in the peripheral nervous system and has been studied for its potential therapeutic applications in conditions like neurodegenerative diseases and nerve injuries.