Akt Kinase-Mediated Checkpoint of cGAS DNA Sensing Pathway

作者：Seo Gil Ju; Yang Aerin; Tan Brandon; Kim Sungyoon; Liang Qiming; Choi Younho; Yuan Weiming; Feng Pinghui; Park Hee Sung; Jung Jae U^*

来源：Cell Reports, 2015, 13(2): 440-449.

DOI：10.1016/j.celrep.7015.09.007

Upon DNA stimulation, cyclic GMP-AMP synthase (cGAS) synthesizes the second messenger cyclic GMP-AMP (cGAMP) that binds to the STING, triggering antiviral interferon-beta (IFN-beta) production. However, it has remained undetermined how hosts regulate cGAS enzymatic activity after the resolution of DNA immunogen. Here, we show that Akt kinase plays a negative role in cGAS-mediated anti-viral immune response. Akt phosphorylated the S291 or S305 residue of the enzymatic domain of mouse or human cGAS, respectively, and this phosphorylation robustly suppressed its enzymatic activity. Consequently, expression of activated Akt led to the reduction of cGAMP and IFN-beta production and the increase of herpes simplex virus 1 replication, whereas treatment with Akt inhibitor augmented cGAS-mediated IFN-beta production. Furthermore, expression of the phosphorylation-resistant cGAS S291A mutant enhanced I FN-beta production upon DNA stimulation, HSV-1 infection, and vaccinia virus infection. Our study identifies an Akt kinase-mediated checkpoint to fine-tune hosts' immune responses to DNA stimulation.

• 出版日期2015-10-13