Homeostatic Regulation of Seizure Susceptibility and Cognitive Function by ER Quality Controller Derlin-1 through Maintenance of Adult Neurogenesis

Abstract

Dysfunction of organelle is closely associated with neurological diseases involving disruption of adult neurogenesis. However, the role of the endoplasmic reticulum (ER)-related molecules in this process remains largely unexplored. Here we show that Derlin-1, an ER quality controller, maintains adult neurogenesis in a spatiotemporal manner. Deletion of Derlin-1 in the mouse central nervous system induces ectopic localization of newborn neurons and impairs neural stem cells (NSCs) transition from active to quiescent states, resulting in early depletion of hippocampal NSCs. As a result, Derlin-1- deficient mice exhibit phenotypes of increased seizure susceptibility and impaired cognitive function. Reduced expression of signal transducer and activator of transcription 5b (Stat5b) was found to be responsible for the impairment of adult neurogenesis in Derlin-1-deficient NSCs. Remarkably, the inhibition of histone deacetylase activity ameliorated seizure susceptibility and cognitive dysfunction in Derlin-1-deficient mice by increasing Stat5b expression and restoring abnormal neurogenesis. Overall, our findings demonstrate that Derlin-1, as its characteristic function, plays an essential role in the homeostasis of adult neurogenesis via Stat5b expression, thus regulating seizure susceptibility and cognitive function.