COPB1 encodes a critical subunit of the coatomer protein complex I (COPI), which mediates vesicle-mediated transport between the endoplasmic reticulum and Golgi apparatus 12. The protein plays essential roles in retrograde transport from Golgi to ER and maintains cellular membrane trafficking homeostasis 3. COPB1 functions in multiple cellular processes including lipid homeostasis, autophagy through early endosome function, and organellar compartmentalization of secretory compartments 1. The protein interacts with various cellular components, including the Vac14-Fig4 complex involved in endosomal maturation and STING signaling pathways 13. Mechanistically, COPB1 knockdown disrupts STING homeostasis, preventing its retrieval from Golgi to ER, which activates type I interferon signaling 3. COPB1 is clinically significant as mutations cause Baralle-Macken syndrome, a rare autosomal recessive neurological disorder affecting early brain development 4. The protein is also implicated in cancer progression, with upregulation promoting breast cancer metastasis through enhanced ER-Golgi trafficking 2, and shows elevated expression across multiple cancer types with poor prognosis 5. COPB1 demonstrates antiviral therapeutic potential, as it is essential for both influenza A virus and SARS-CoV-2 infection 6.