The innate immune system protects the host from external pathogens and internal damage in various ways. The cGAS-STING signaling pathway,comprised of cyclic GMP-AMP synthase(cGAS),stimulator of interferon genes(STING)...The innate immune system protects the host from external pathogens and internal damage in various ways. The cGAS-STING signaling pathway,comprised of cyclic GMP-AMP synthase(cGAS),stimulator of interferon genes(STING), and downstream signaling adaptors, plays an essential role in protective immune defense against microbial DNA and internal damaged-associated DNA and is responsible for various immune-related diseases.After binding with DNA, cytosolic cGAS undergoes conformational change and DNA-linked liquid-liquid phase separation to produce 2’3’-c GAMP for the activation of endoplasmic reticulum(ER)-localized STING. However, further studies revealed that cGAS is predominantly expressed in the nucleus and strictly tethered to chromatin to prevent binding with nuclear DNA, and functions differently from cytosoliclocalized cGAS. Detailed delineation of this pathway,including its structure, signaling, and regulatory mechanisms, is of great significance to fully understand the diversity of cGAS-STING activation and signaling and will be of benefit for the treatment of inflammatory diseases and cancer. Here, we review recent progress on the above-mentioned perspectives of the cGAS-STING signaling pathway and discuss new avenues for further study.展开更多
The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically revie...The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically reviewed.Here,we outline the components of the cGAS–STING pathway and then analyze its role in autophagy,ferroptosis,cellular pyroptosis,disequilibrium of calcium homeostasis,inflammatory responses,disruption of the blood–brain barrier,microglia transformation,and complement system activation following cerebral ischemia-reperfusion injury.We further analyze the value of cGAS–STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple mechanisms.Inhibition of the cGAS–STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury.展开更多
AIM:To explore the expression of cGAS/STING signaling components in Mooren’s ulcer(MU).METHODS:Samples were obtained from ten MU patients,and eight residual corneal-scleral rings of healthy donor corneas for controls...AIM:To explore the expression of cGAS/STING signaling components in Mooren’s ulcer(MU).METHODS:Samples were obtained from ten MU patients,and eight residual corneal-scleral rings of healthy donor corneas for controls.Human corneal epithelial cells(HCECs)were used to evaluate the effect of cGAS/STING signaling pathway.Immunohistochemistr y(IHC)and Western blot were used to examine the expression of cGAS,STING,and phosphorylated interferon regulatory factor 3(p-IRF3)in MU tissues.The expression of interferon-β(IFN-β)and interferon-stimulated genes(ISGs)was quantified by real-time polymerase chain reaction(PCR)and enzymelinked immunosorbent assay(ELISA).RESULTS:The protein levels of cGAS and STING in MU samples were significantly elevated when compared with the healthy controls by Western blot and IHC.After stimulation with cGAMP,real-time PCR and ELISA showed a dramatic increase of IFN-βand ISGs(containing CXCL10,IFIT1,and IL-6)in HCECs.Moreover,HCECs treated with cGAMP was characterized by increased phosphorylation and more nuclear translocation of IRF3.Meanwhile,increased p-IRF3 was observed in MU samples via IHC and Western blot.CONCLUSION:The pronounced expression of cGAS/STING signaling components in the patients with MU and probably contribute to the onset and development of MU.展开更多
African swine fever virus(ASFV)is an important pathogen causing acute infectious disease in domestic pigs and wild boars that seriously endangers the global swine industry.As ASFV is structurally complex and encodes a...African swine fever virus(ASFV)is an important pathogen causing acute infectious disease in domestic pigs and wild boars that seriously endangers the global swine industry.As ASFV is structurally complex and encodes a large number of functional proteins,no effective vaccine has been developed to date.Thus,dissecting the mechanisms of immune escape induced by ASFV proteins is crucial.A previous study showed that the ASFV-encoded protein is an important factor in host immunity.In this study,we identified a negative regulator,MGF505-3R,that significantly downregulated cGAS/STING-and poly(dG:dC)-mediated IFN-βand interferon stimulation response element(ISRE)reporter activity and suppressed IFNB1 and IFIT2 mRNA levels.In addition,TBK1,IRF3 and IκBαphosphorylation levels were also inhibited.Mechanistically,MGF505-3R interacted with cGAS/TBK1/IRF3 and targeted TBK1 for degradation,thereby disrupting the cGAS-STING-mediated IFN-βsignaling pathway,which appears to be highly correlated with autophagy.Knockdown MGF505-3R expression enhanced IFN-βand IL-1βproduction.Taken together,our study revealed a negative regulatory mechanism involving the MGF505-3R-cGAS-STING axis and provided insights into an evasion strategy employed by ASFV that involves autophagy and innate signaling pathways.展开更多
基金supported by the Natural Science Foundation of Zhejiang Province(LY23C190002)National Natural Science Foundation of China(32173004)Natural Science Foundation of Ningbo City(202003N4011)。
文摘The innate immune system protects the host from external pathogens and internal damage in various ways. The cGAS-STING signaling pathway,comprised of cyclic GMP-AMP synthase(cGAS),stimulator of interferon genes(STING), and downstream signaling adaptors, plays an essential role in protective immune defense against microbial DNA and internal damaged-associated DNA and is responsible for various immune-related diseases.After binding with DNA, cytosolic cGAS undergoes conformational change and DNA-linked liquid-liquid phase separation to produce 2’3’-c GAMP for the activation of endoplasmic reticulum(ER)-localized STING. However, further studies revealed that cGAS is predominantly expressed in the nucleus and strictly tethered to chromatin to prevent binding with nuclear DNA, and functions differently from cytosoliclocalized cGAS. Detailed delineation of this pathway,including its structure, signaling, and regulatory mechanisms, is of great significance to fully understand the diversity of cGAS-STING activation and signaling and will be of benefit for the treatment of inflammatory diseases and cancer. Here, we review recent progress on the above-mentioned perspectives of the cGAS-STING signaling pathway and discuss new avenues for further study.
基金supported by Yuan Du Scholars,Clinical Research Center of Affiliated Hospital of Shandong Second Medical University,No.2022WYFYLCYJ02Weifang Key Laboratory,Weifang Science and Technology Development Plan Project Medical Category,No.2022YX093.
文摘The cGAS–STING pathway plays an important role in ischemia-reperfusion injury in the heart,liver,brain,and kidney,but its role and mechanisms in cerebral ischemia-reperfusion injury have not been systematically reviewed.Here,we outline the components of the cGAS–STING pathway and then analyze its role in autophagy,ferroptosis,cellular pyroptosis,disequilibrium of calcium homeostasis,inflammatory responses,disruption of the blood–brain barrier,microglia transformation,and complement system activation following cerebral ischemia-reperfusion injury.We further analyze the value of cGAS–STING pathway inhibitors in the treatment of cerebral ischemia-reperfusion injury and conclude that the pathway can regulate cerebral ischemia-reperfusion injury through multiple mechanisms.Inhibition of the cGAS–STING pathway may be helpful in the treatment of cerebral ischemia-reperfusion injury.
基金Supported by National Natural Science Foundation of China(No.81900907)the Young and Middle-Aged Scientists Research Awards Fund of Shandong Province(No.ZR2017BH004)。
文摘AIM:To explore the expression of cGAS/STING signaling components in Mooren’s ulcer(MU).METHODS:Samples were obtained from ten MU patients,and eight residual corneal-scleral rings of healthy donor corneas for controls.Human corneal epithelial cells(HCECs)were used to evaluate the effect of cGAS/STING signaling pathway.Immunohistochemistr y(IHC)and Western blot were used to examine the expression of cGAS,STING,and phosphorylated interferon regulatory factor 3(p-IRF3)in MU tissues.The expression of interferon-β(IFN-β)and interferon-stimulated genes(ISGs)was quantified by real-time polymerase chain reaction(PCR)and enzymelinked immunosorbent assay(ELISA).RESULTS:The protein levels of cGAS and STING in MU samples were significantly elevated when compared with the healthy controls by Western blot and IHC.After stimulation with cGAMP,real-time PCR and ELISA showed a dramatic increase of IFN-βand ISGs(containing CXCL10,IFIT1,and IL-6)in HCECs.Moreover,HCECs treated with cGAMP was characterized by increased phosphorylation and more nuclear translocation of IRF3.Meanwhile,increased p-IRF3 was observed in MU samples via IHC and Western blot.CONCLUSION:The pronounced expression of cGAS/STING signaling components in the patients with MU and probably contribute to the onset and development of MU.
基金supported by the National Natural Science Foundation of China(31941018,32072888,U21A20261)China Agriculture Research System of MOF and MARA(CARS-35)+1 种基金Science and Technology Development Program of Jilin Province(YDZJ202102CXJD029,20190301042NY,20200402041NC)Science and Technology Development Program of Changchun City(21ZY42).
文摘African swine fever virus(ASFV)is an important pathogen causing acute infectious disease in domestic pigs and wild boars that seriously endangers the global swine industry.As ASFV is structurally complex and encodes a large number of functional proteins,no effective vaccine has been developed to date.Thus,dissecting the mechanisms of immune escape induced by ASFV proteins is crucial.A previous study showed that the ASFV-encoded protein is an important factor in host immunity.In this study,we identified a negative regulator,MGF505-3R,that significantly downregulated cGAS/STING-and poly(dG:dC)-mediated IFN-βand interferon stimulation response element(ISRE)reporter activity and suppressed IFNB1 and IFIT2 mRNA levels.In addition,TBK1,IRF3 and IκBαphosphorylation levels were also inhibited.Mechanistically,MGF505-3R interacted with cGAS/TBK1/IRF3 and targeted TBK1 for degradation,thereby disrupting the cGAS-STING-mediated IFN-βsignaling pathway,which appears to be highly correlated with autophagy.Knockdown MGF505-3R expression enhanced IFN-βand IL-1βproduction.Taken together,our study revealed a negative regulatory mechanism involving the MGF505-3R-cGAS-STING axis and provided insights into an evasion strategy employed by ASFV that involves autophagy and innate signaling pathways.
