CRISPR screening identifies GNPTAB as a noncanonical STING activator driving cellular senescence

Cellular senescence is accompanied by profound lysosomal alterations, yet whether lysosome-associated factors actively drive aging remains unclear. Through a focused CRISPR/Cas9 screen in human mesenchymal progenitor cells (hMPCs), we identified GNPTAB, an enzyme responsible for lysosomal hydrolase targeting, as a potent regulator of cellular senescence. Genetic ablation of GNPTAB attenuated senescence, whereas its overexpression accelerated aging. This pro-senescent function occurred independently of GNPTAB’s canonical enzymatic role. Instead, GNPTAB binds to the innate immune adaptor STING via a specific interface (E1119), leading to activation of STING and its downstream TANK-binding kinase 1 (TBK1) activation and pro-inflammatory gene expression. A STING-binding-deficient GNPTAB mutant (E1119A) preserved enzymatic function but failed to induce senescence, while STING depletion abolished GNPTAB-driven senescence. Together, these findings uncover a non-canonical, lysosome-to-immune signaling pathway wherein GNPTAB directly engages STING to facilitate its activation, nominating this interface as a potential target for mitigating age-related cellular dysfunction.