Charcot‐Marie‐Tooth disease is the most common inherited peripheral neuropathy. Dominant mutations in the glycyl‐tRNA synthetase (GARS) gene cause peripheral nerve degeneration and lead to CMT disease type 2D. The underlying mechanisms of mutations in GARS (GARSCMT2D) in disease pathogenesis are not fully understood. In this study, we report that wild‐type GARS binds the NAD+‐dependent deacetylase SIRT2 and inhibits its deacetylation activity, resulting in the acetylated α‐tubulin, the major substrate of SIRT2. The catalytic domain of GARS tightly interacts with SIRT2, which is the most CMT2D mutation localization. However, CMT2D mutations in GARS cannot inhibit SIRT2 deacetylation, which leads to a decrease of acetylated α‐tubulin. Genetic reduction of SIRT2 in the Drosophila model rescues the GARS‐induced axonal CMT neuropathy and extends the life span. Our findings demonstrate the pathogenic role of SIRT2‐dependent α‐tubulin deacetylation in mutant GARS‐induced neuropathies and provide new perspectives for targeting SIRT2 as a potential therapy against hereditary axonopathies.

Charcot-Marie-Tooth disease is the most common inherited peripheral neuropathy. Dominant mutations in glycyl-tRNA synthetase (GARS) gene cause peripheral nerve degeneration and lead to CMT disease type 2D. Mutations in GARS (GARS CMT2D ) show partial loss-of-function features, suggesting that tRNA-charging deficits play a role in disease pathogenesis, but the underlying mechanisms are not fully understood. In this study we report that wild-type GARS tightly binds the NAD + -dependent deacetylase SIRT2 and inhibits its deacetylation activity, resulting in the hyperacetylated -tubulin, the major substrate of SIRT2. Previous studies showed that acetylation of-tubulin protects microtubules from mechanical breakage and keep axonal transportation. However, CMT2D mutations in GARS can not inhibit SIRT2 deacetylation, which leads to decrease acetylated -tubulin and severe axonal transport deficits. Genetic reduction of SIRT2 in the Drosophila model rescues the GARS-induced axonal CMT neuropathy and extends the life span. Our findings demonstrate the pathogenic role of SIRT2-dependent -tubulin deacetylation in mutant GARS-induced neuropathies and provide new perspectives for targeting SIRT2 as a potential therapy against hereditary axonopathies.