NGF (nerve growth factor; HGNC:7808, NCBI Gene ID 4803) is a human locus mapped to chromosome band 1p13.2 that encodes Pro-NGF precursor (241 aa) cleaved to mature homodimeric beta-NGF (120 aa). NGF acts in TrkA (NTRK1) & p75NTR neurotrophic survival and peripheral nociceptor sensitization, together with NTRK1 (TrkA Receptor Gene), BDNF (Brain-Derived Neurotrophic Factor), and Growth Factors. Encodes nerve growth factor (beta-NGF), essential for nociceptive and sympathetic neuron survival and pain sensitization.
TrkA (NTRK1) & p75NTR neurotrophic survival and peripheral nociceptor sensitization
Clinical / Therapeutic Role
Hereditary sensory and autonomic neuropathy type V (HSAN5); anti-NGF antibody pain target
Gene Structure & Expression
Genomic Organization & Cytogenetic Locus: 3-exon gene on chromosome 1p13.2 encoding a 241-amino-acid preproprotein with an N-terminal pro-peptide that is proteolytically cleaved by furin or plasmin to yield the cystine-knot beta-NGF monomer, which associates as a non-covalent homodimer.
Cellular & Tissue Expression Profile: Synthesized by peripheral target tissues innervated by sympathetic and nociceptive fibers, basal forebrain cholinergic target neurons in the hippocampus and cerebral cortex, and activated mast cells, macrophages, and keratinocytes at sites of tissue injury.
Molecular Function & Pathways
Biochemical & Physiological Mechanism: Binds the high-affinity receptor tyrosine kinase TrkA (encoded by NTRK1) and the pan-neurotrophin receptor p75NTR (NGFR), undergoing retrograde axonal transport in signaling endosomes to promote neuronal survival during development and sensitizing adult nociceptors by up-regulating TRPV1, SCN9A (Nav1.7), SCN10A (Nav1.8), and TAC1.
Clinical & Therapeutic Significance
Human Genetic Variants & Disease Phenotypes: Homozygous missense mutation p.Arg221Trp (the Norrbottnian Swedish variant) impairs pro-NGF processing and selective nociceptive signaling, causing hereditary sensory and autonomic neuropathy type V (HSAN5) with congenital loss of deep pain perception and Charcot joints without intellectual disability.
Therapeutic & Clinical Pharmacology: Discovered by Rita Levi-Montalcini and Stanley Cohen (1986 Nobel Prize); humanized anti-NGF monoclonal antibodies (tanezumab, fasinumab) demonstrated potent analgesia in osteoarthritis and chronic low back pain while recombinant human NGF (cenegermin) is approved for neurotrophic keratitis.