TARDBP and amyotrophic lateral sclerosis: Transactive response DNA-binding protein 43 (TDP-43) is a key factor in motor neurons and related neurodegenerative disorders, and the presence of cytoplasmic aggregates of TDP-43 is a major hallmark of diseases such amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD).