An alternatively spliced STING isoform localizes in the cytoplasmic membrane and directly senses extracellular cGAMP.

ABSTRACT: It has been revealed that 2'3'-cyclic-GMP-AMP (cGAMP), a second messenger that activates the antiviral stimulator of IFN genes (STING), elicits an antitumoral immune response. Since cGAMP cannot cross the cell membrane, it is not clear how intracellular STING has been activated by extracellular cGAMP until SLC19A1 was identified as an importer to transport extracellular cGAMP into the cytosol. However, SLC19A1-deficient cells also sense extracellular cGAMP, suggesting the presence of mechanisms other than the facilitating transporters for STING sensing extracellular cGAMP. Here, using immunoprecipitation, immunofluorescence, and flow cytometry, we identified an alternatively spliced STING isoform, plasmatic membrane STING (pmSTING), that localized in the plasma membrane with its C-terminus

SUBMITTER: Li X 

PROVIDER: S-EPMC8803335 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature