On the other hand, coat protein complex I (COP-I) mediates the retrograde transport of STING1 to the ERGIC from Golgi, while deficiency in COP-I transport causes failure of Golgi-to-ER STING1 retrieval and ligand-independent activation of STING1, thus contributing to COPA syndrome (37–40) (Figure 2). This evidence concerns the gene STING1 and autoimmune interstitial lung disease-arthritis syndrome.