Knockdown of glutathione S-transferase leads to mislocalization and accumulation of cabeza, a drosophila homolog of FUS, in the brain

Glutathione S-transferase omega (GSTO) is an antioxidant enzyme involved in reducing oxidative stress. Recent studies suggest that polymorphic variants of GSTOs affect the onset age and progression of neurodegenerative diseases. Although GSTO activity may affect the development and age dependency of several diseases, the mechanism by which GSTO inactivation in neurons regulates the susceptibility to neurodegenerative diseases is unclear. In the present study, GstO2 knockdown in Drosophila led to increased levels of Cabeza (Caz) protein in neurons in an age-dependent manner. Drosophila Caz is the ortholog of human FUS, which is associated with neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). We found that cytoplasmic Caz mislocalization and aggregation in neurons significantly increased after GstO2 knockdown in vivo. Downregulation of GstO2 decreased the solubility of the Caz protein in aging neurons. These findings demonstrate that GSTO is a critical modulator of the development of neurodegenerative diseases by regulating Caz localization and aggregation in the nervous system of Drosophila.