Caspase-3 Control of RNA Splicing and Mitochondrial Dynamics in Microglia during Parkinson’s Disease

These novel functions appear to depend on distinct levels of caspase-3 activation; however, the role of basal caspase-3 activity remains unclear. Here, we show that basal caspase-3 regulates RNA splicing in microglia, and its inhibition in a Parkinson´s disease (PD) model leads to splicing dysregulation.

Loss of basal caspase-3 activity also increases double-stranded RNA (dsRNA) accumulation, inducing a type I interferon response. Additionally, caspase-3 deficiency impairs mitochondrial respiration, reduces ATP production, and causes sex-specific mitochondrial abnormalities, predominantly in female microglia. Together, our findings uncover a non-apoptotic, homeostatic role for basal caspase-3 activity in microglia.