Low-affinity nerve growth factor receptor

The Low-Affinity Nerve Growth Factor Receptor (nerve growth factor receptor (TNFR superfamily, member 16), also called the LNGFR or p75 neurotrophin receptor) is one of the two receptor types for the neurotrophins, a family of protein growth factors that stimulate neuronal cells to survive and differentiate. LNGFR is a member of the tumor necrosis factor receptor (TNF receptor)superfamily - indeed, LNGFR was the first member of this large family of receptors to be characterized.

Neurotrophins

The neurotrophins are composed of four proteins, all of which bind to the LNGFR: Nerve Growth Factor (NGF), Brain Derived Neurotrophic Factor (BDNF), Neurotrophin-3 (NT-3), and Neurotrophin-4 (NT-4).

Nerve growth factor, the prototypical growth factor, is a protein secreted by a neuron's target. NGF is critical for the survival and maintenance of sympathetic and sensory neurons. NGF is released from the target cells, binds to and activates its high-affinity receptor (TrkA), and is internalized into the responsive neuron. The NGF/TrkA complex is subsequently trafficked back to the cell body. This movement of NGF from axon tip to soma is thought to be involved in the long-distance signaling of neurons.