Figure 4.

Disease-associated mutant of STING activates SEMA4D shedding. A and B, STING^−/− Raw264.7 cells expressing the Tet-on–STING-FLAG WT or Tet-on–STING-FLAG V146L mutant (V146L) were cultured in 0.1% FCS/DMEM with or without 1 μg/ml doxycycline (DOX) for 4 h. In A, the cells were fixed and co-stained with anti-FLAG and anti-GM130 antibodies followed by examination under confocal microscopy. Scale bars, 5 μm. In B, the culture supernatants and the cell lysates were analyzed by Western blotting with anti-SEMA4D, anti-phospho-TBK1, anti-STING, or anti-α-tubulin.