Interferons(IFNs)play an important role in immunomodulatory and antiviral functions.IFN-induced necroptosis has been reported in cells deficient in receptor-interacting protein kinase 1(RIPK1),Fas-associated protein w...Interferons(IFNs)play an important role in immunomodulatory and antiviral functions.IFN-induced necroptosis has been reported in cells deficient in receptor-interacting protein kinase 1(RIPK1),Fas-associated protein with death domain(FADD),or caspase-8,but the mechanism is largely unknown.Here,we report that the DNA-dependent activator of IFN regulatory factors(ZBP1,also known as DAI)is required for both type Ⅰ(β)and type Ⅱ(γ)IFN-induced necroptosis.We show that L929 fibroblast cells became susceptible to IFN-induced necroptosis when RIPK1,FADD,or Caspase-8 was genetically deleted,confirming the antinecroptotic role of these proteins in IFN signaling.We found that the pronecroptotic signal from IFN stimulation depends on new protein synthesis and identified ZBP1,an IFN-stimulated gene(ISG)product,as the de novo synthesized protein that triggers necroptosis in IFN-stimulated cells.The N-terminal domain(ND)of ZBP1 is important for ZBP1–ZBP1 homointeraction,and its RHIM domain in the C-terminal region interacts with RIPK3 to initiate RIPK3-dependent necroptosis.The antinecroptotic function of RIPK1,FADD,and caspase-8 in IFN-treated cells is most likely executed by caspase-8-mediated cleavage of RIPK3,since the inhibitory effect on necroptosis was eliminated when the caspase-8 cleavage site in RIPK3 was mutated.ZBP1-mediated necroptosis in IFN-treated cells is likely physiologically relevant,as ZBP1 KO mice were significantly protected against acute systemic inflammatory response syndrome(SIRS)induced by TNF+IFN-γ.展开更多
基金supported by the National Natural Science Foundation of China(81788101)the National Basic Research Program of China(973 Program 2015CB553800)+3 种基金the National Natural Science Foundation of China(31420103910,81630042,31500737,and 31601122)the China Postdoctoral Science Foundation(2018T110638,2017 M620267,and 2015T80680)the 111 Project(B12001)the National Science Foundation of China for Fostering Talents in Basic Research(J1310027).
文摘Interferons(IFNs)play an important role in immunomodulatory and antiviral functions.IFN-induced necroptosis has been reported in cells deficient in receptor-interacting protein kinase 1(RIPK1),Fas-associated protein with death domain(FADD),or caspase-8,but the mechanism is largely unknown.Here,we report that the DNA-dependent activator of IFN regulatory factors(ZBP1,also known as DAI)is required for both type Ⅰ(β)and type Ⅱ(γ)IFN-induced necroptosis.We show that L929 fibroblast cells became susceptible to IFN-induced necroptosis when RIPK1,FADD,or Caspase-8 was genetically deleted,confirming the antinecroptotic role of these proteins in IFN signaling.We found that the pronecroptotic signal from IFN stimulation depends on new protein synthesis and identified ZBP1,an IFN-stimulated gene(ISG)product,as the de novo synthesized protein that triggers necroptosis in IFN-stimulated cells.The N-terminal domain(ND)of ZBP1 is important for ZBP1–ZBP1 homointeraction,and its RHIM domain in the C-terminal region interacts with RIPK3 to initiate RIPK3-dependent necroptosis.The antinecroptotic function of RIPK1,FADD,and caspase-8 in IFN-treated cells is most likely executed by caspase-8-mediated cleavage of RIPK3,since the inhibitory effect on necroptosis was eliminated when the caspase-8 cleavage site in RIPK3 was mutated.ZBP1-mediated necroptosis in IFN-treated cells is likely physiologically relevant,as ZBP1 KO mice were significantly protected against acute systemic inflammatory response syndrome(SIRS)induced by TNF+IFN-γ.
