Crystal structures of STING protein reveal basis for recognition of cyclic di-GMP.

State Key Laboratory of Microbial Technology, School of Life Science, Shandong University, Jinan, China.
Nature Structural & Molecular Biology (Impact Factor: 11.63). 06/2012; 19(7):725-7. DOI: 10.1038/nsmb.2332
Source: PubMed

ABSTRACT STING functions as both an adaptor protein signaling cytoplasmic double-stranded DNA and a direct immunosensor of cyclic diguanylate monophosphate (c-di-GMP). The crystal structures of the C-terminal domain of human STING (STING(CTD)) and its complex with c-di-GMP reveal how STING recognizes c-di-GMP. In response to c-di-GMP binding, two surface loops, which serve as a gate and latch of the cleft formed by the dimeric STING(CTD), undergo rearrangements to interact with the ligand.

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