INA (internexin neuronal intermediate filament protein, α) gene encodes a type-IV neuronal intermediate filament th at functions in the morphogenesis of neurons. It is present within the pathological inclusions of NIFID (Neuronal intermediate filament inclusion disease) along with heavy, medium, and light neurofilament subunits (NF-L, NF-M, and NF-H). The disease is characterized by frontotemporal dementia, pyramidal, and extrapyramidal signs. α-Internexin serves as a prognostic biomarker for pancreatic neuroendocrine tumor aggressiveness.
