DNA sensing and timely activation of interferon(IFN)-mediated innate immunity are crucial for the defense against DNA virus infections and the clearance of abnormal cells.However,overactivation of immune responses may...DNA sensing and timely activation of interferon(IFN)-mediated innate immunity are crucial for the defense against DNA virus infections and the clearance of abnormal cells.However,overactivation of immune responses may lead to tissue damage and autoimmune diseases;therefore,these processes must be intricately regulated.STING is the key adaptor protein,which is activated by cyclic GMP-AMP,the second messenger derived from cGAS-mediated DNA sensing.Here,we report that CCDC50,a newly identified autophagy receptor,tunes STING-directed type I IFN signaling activity by delivering K63-polyubiquitinated STING to autolysosomes for degradation.Knockout of CCDC50 significantly increases herpes simplex virus 1(HSV-1)-or DNA ligand-induced production of type I IFN and proinflammatory cytokines.Ccdc50-deficient mice show increased production of IFN,decreased viral replication,reduced cell infiltration,and improved survival rates compared with their wild-type littermates when challenged with HSV-1.Remarkably,the expression of CCDC50 is downregulated in systemic lupus erythematosus(SLE),a chronic autoimmune disease.CCDC50 levels are negatively correlated with IFN signaling pathway activation and disease severity in human SLE patients.CCDC50 deficiency potentiates the cGAS-STING-mediated immune response triggered by SLE serum.Thus,our findings reveal the critical role of CCDC50 in the immune regulation of viral infections and autoimmune diseases and provide insights into the therapeutic implications of CCDC50 manipulation.展开更多
基金This study is supported by the National Natural Science Foundation of China(#81620108020 to DG and#81801574 to PH)Guangdong Province"Pearl River Talent Plan"Innovation and Entrepreneurship Team Project(2019ZT08Y464 to CL)+1 种基金Shenzhen Science and Technology Program(#JCYJ20200109142201695 and#KQTD20180411143323605 to DG and#JCYJ20190807161415336 to PH)DG is also supported by the Guangdong Zhujiang Talents Programme and the National Ten-thousand Talents Programme.
文摘DNA sensing and timely activation of interferon(IFN)-mediated innate immunity are crucial for the defense against DNA virus infections and the clearance of abnormal cells.However,overactivation of immune responses may lead to tissue damage and autoimmune diseases;therefore,these processes must be intricately regulated.STING is the key adaptor protein,which is activated by cyclic GMP-AMP,the second messenger derived from cGAS-mediated DNA sensing.Here,we report that CCDC50,a newly identified autophagy receptor,tunes STING-directed type I IFN signaling activity by delivering K63-polyubiquitinated STING to autolysosomes for degradation.Knockout of CCDC50 significantly increases herpes simplex virus 1(HSV-1)-or DNA ligand-induced production of type I IFN and proinflammatory cytokines.Ccdc50-deficient mice show increased production of IFN,decreased viral replication,reduced cell infiltration,and improved survival rates compared with their wild-type littermates when challenged with HSV-1.Remarkably,the expression of CCDC50 is downregulated in systemic lupus erythematosus(SLE),a chronic autoimmune disease.CCDC50 levels are negatively correlated with IFN signaling pathway activation and disease severity in human SLE patients.CCDC50 deficiency potentiates the cGAS-STING-mediated immune response triggered by SLE serum.Thus,our findings reveal the critical role of CCDC50 in the immune regulation of viral infections and autoimmune diseases and provide insights into the therapeutic implications of CCDC50 manipulation.