Figure 1.
cGAMP can be detected but not quantitated by pairing ENPP1 with commercially available AMP quantitation kits. A, scheme of cGAMP-Luc assay. B, purification of ENPP1 by size-exclusion chromatography. C, 2′3′-cGAMP hydrolysis reaction monitored by TLC assay and visualized by autoradiography. Data are representative of three independent experiments. D, cGAMP standard curve generated by ENPP1 and AMP-GloTM. Data are mean ± S.E. (error bars) (n = 2). E, AMP standard curve generated by AMP-GloTM. Data are mean ± S.E. (n = 4) with error bars too small to visualize. F, ATP standard curve generated by CellTiter-Glo®. Data are mean ± S.E. (n = 3) with error bars too small to visualize.