Figure 1.

Overview of the cGAS-STING pathway in age-related diseases. cGAS is a cytosolic DNA sensor that detects dsDNA from senescent cells and dead cells, and some extracellular dsDNA, mtDNA and DNA in the micronuclei are also the main sources of cytosolic DNA. After combining with DNA, cGAS interacts with GTP and ATP, inducing the synthesis of cGAMP. In addition to intracellular synthesis, extracellular cGAMP can also enter the cell and acts as a second messenger, binding to STING located in the ER. Activated STING then transfers to the Golgi via ERGIC, where it can truly function, interacting with TBK1, IRF3, and NF-κB and mediating the production of type I IFN, SASP and ISG, promoting the inflammatory response and exerting biological effects.