The goal of treating central nervous system (CNS) disorders requires understanding not only of neuronal dysfunction but also of how other CNS cells respond to and impact neuronal dysfunction. Astrocytes and microglia play fundamental roles in nearly all aspects of neuronal function. In reaction to neuronal pathology, they undergo activation, a profound cellular process whose functional significance is still a matter of debate. Glial activation is implicated in spinocerebellar ataxia type 1 (SCA1) - a fatal, dominantly inherited neurodegenerative disease of the cerebellum caused by the expansion of CAG repeats in the Ataxin-1 (ATXN1) gene. Despite an intense focus on neuronal pathology, the cellular and molecular mechanisms of SCA1 remain incompletely understood. The long-term objective of this research program is to investigate the function of glia in the pathogenesis of SCA1.