Cyclic di-GMP is a second messenger in bacteria involved in diverse prokaryotic processes, including biofilm formation, motility, virulence, and cell cycling.1,2 In eukaryotic cells, cyclic di-GMP is detected by and binds to the transmembrane protein stimulator of interferon genes (STING; Kd = 1.21 ?M), leading to activation of the innate immune system.3,4 It has been used at a preset molar ratio with STING dimers in binding assays to determine the binding constants of particularly tight binding partners, such as 2’3’-cGAMP. Cyclic di-GMP induces IFN-β mRNA expression in vitro (EC50 = 537.8 nM) but less potently than 2’3’-cGAMP , 3’2’-cGAMP, 3’3’-cGAMP , and 2’2’-cGAMP .
1.R?mling, U., Galperin, M.Y., and Gomelsky, M.Cyclic di-GMP: The first 25 years of a universal bacterial second messengerMicrobiol. Mol. Biol. Rev.77(1)1-52(2013) 2.Martínez, L.C., and Vadyvaloo, V.Mechanisms of post-transcriptional gene regulation in bacterial biofilmsFront. Cell. Neurosci.4(38)1-15(2014) 3.Schaap, P.Cyclic di-nucleotide signaling enters the eukaryote domainIUBMB Life65(11)897-903(2013) 4.Zhang, X., Shi, H., Wu, J., et al.Cyclic GMP-AMP containing mixed phosphodiester linkages is an endogenous high-affinity ligand for STINGMol. Cell51(2)226-235(2013)