G6PD facilitates axon regeneration via clathrin-mediated endocytosis.

Metabolic reprogramming is a hallmark of neuronal repair, yet the roles of glucose metabolism-related enzymes remain poorly understood. To investigate their functions, we employed a sciatic nerve injury model, taking advantage the intrinsic regenerative capacity of peripheral neurons. After sciatic nerve crush injury, dorsal root ganglia exhibited sustained upregulation of several enzymes in the pentose phosphate pathway. Notably, glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the pentose phosphate pathway, was markedly increased at both RNA and protein levels. Silencing G6PD impaired axon regeneration in vitro and in vivo, whereas its overexpression enhanced regrowth. Interestingly, G6PD overexpression did not alter the NADP(+)/NADPH ratio, suggesting a nonmetabolic role. Using mass spectrometry, coimmunoprecipitation, and Duolink proximity ligation assays, we identified clathrin heavy chain as a specific binding partner of G6PD. Mechanistic analyses further showed that G6PD facilitated neuronal endocytosis through direct interaction with clathrin heavy chain, thereby promoting axon regeneration. These findings identify G6PD as a molecular link between metabolic reprogramming and membrane trafficking, revealing an unexpected nonmetabolic role in neural repair.