ATP6V1G3 encodes a subunit of the V1 complex of vacuolar H+-ATPase (V-ATPase), which functions as a proton pump for cellular acidification 1. This gene shows highly tissue-specific expression patterns, being selectively enriched in kidney intercalated cells where it serves as a specific marker for studying acid-base homeostasis 2. ATP6V1G3 is also expressed in ionocytes, rare epithelial cells with high CFTR expression, where it contributes to ion transport regulation 3. The protein demonstrates diagnostic utility as an immunohistochemical marker, showing strong diffuse positivity in chr1 renal cell carcinoma (100% of cases) but absent expression in clear cell and papillary RCC subtypes 4. In disease contexts, ATP6V1G3 exhibits altered expression in multiple pathological conditions. In hepatic fibrosis, its inhibition promotes hepatic stellate cell senescence through the Notch1 pathway, suggesting therapeutic potential 5. The gene shows upregulation in glioblastoma and correlates with poor patient survival, indicating its role in cancer progression 1. Additionally, ATP6V1G3 has been identified as a hub gene in recurrent spontaneous abortion through bioinformatics analysis 6 and shows altered expression in osteosarcoma 7. These findings highlight ATP6V1G3's importance in both normal physiology and disease pathogenesis.