TDP-43 impairs glycolysis by sequestering hexokinase 1 in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder characterized by progressive motor neuron degeneration and cytoplasmic mislocalization of TDP-43. While metabolic dysfunction is increasingly recognized in ALS, the mechanistic link between impaired energy metabolism and TDP-43 pathology remains unknown. Here, we show that cytoplasmic TDP-43 directly disrupts glycolysis by targeting hexokinase 1 (HK1), the first rate-limiting enzyme of the pathway. In cells expressing a TDP-43 variant lacking its nuclear localization signal and in patient-derived iPSC motor neurons, TDP-43 accumulation in the cytoplasm reduces glycolytic capacity, indicating a neuron-intrinsic metabolic defect. Across cellular models including patient-derived neurons, TDP-43 mutant mice, and postmortem spinal cord tissue from ALS patients, we observe consistent decreases in HK1 protein level, mitochondrial association, and enzymatic activity, despite unchanged transcript levels. Mechanistically, cytoplasmic TDP-43 directly binds to HK1, disassociating it from mitochondria and promoting its sequestration into insoluble aggregates. This mislocalization impairs glycolysis and increases neuronal vulnerability. Notably, compensation for HK1 loss reduces cytoplasmic TDP-43 and ubiquitin accumulation, improves motor performance, and prolongs survival in TDP-43-associated ALS models. Together, these findings identify a previously unrecognized mechanism by which TDP-43 impairs glycolysis through HK1 misregulation and highlight glycolytic restoration as a potential therapeutic strategy in ALS.