Background: TAR DNA-binding protein 43 (TDP-43) is a nuclear protein,but it is redistributed in the neuronal cytoplasm in both amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD).Because small transgenic animal models often lack cytoplasmic TDP-43,how the cytoplasmic accumulation of TDP-43 contributes to these diseases remains unclear.The current study is aimed at studying the mechanism of cytoplasmic pathology of TDP-43.