We have investigated beta interferon (IFN-β) and IFN-α4 gene expression and activation of related transcription factors in mouse cytomegalovirus (MCMV)-infected fibroblasts. mRNA analysis demonstrated an initial phase of IFN gene induction upon MCMV infection, which was followed by a sustained MCMV-mediated simultaneous downregulation of IFN-β and IFN-α4 gene expression. The induction of IFN transcription resulted from the activation of the components of the IFN-β enhanceosome, i.e. IFN regulatory factor (IRF) 3, nuclear factor (NF)-κB, activating transcription factor (ATF)-2 and c-Jun. Activation of the transcription factors occurred rapidly and in a sequential order upon infection, but only lasted a while. As a consequence, IFN-α/β gene expression became undetectable 6 h post-infection and throughout the MCMV replication cycle. This effect is based on an active interference since restimulation of IFN gene induction by further external stimuli (e.g. Sendai virus infection) was completely abolished. This inhibition required MCMV gene expression and was not observed in cells infected with UV-inactivated MCMV virions. The efficiency of inhibition is achieved by a concerted blockade of IκBα degradation and a lack of nuclear accumulation of IRF3 and ATF-2/c-Jun. Using an MCMV mutant lacking pM27, a signal transducer and activator of transcription (STAT) 2-specific inhibitor of Jak/STAT signalling, we found that the initial phase of IFN induction and the subsequent inhibition does not depend on the positive-IFN feedback loop. Our findings indicate that the MCMV-mediated downregulation of IFN transcription in fibroblasts relies on a large arsenal of inhibitory mechanisms targeting each pathway that contributes to the multiprotein enhanceosome complex.
AbateD. A.,
WatanabeS.,
MocarskiE. S.2004; Major human cytomegalovirus structural protein pp65 (ppUL83) prevents interferon response factor 3 activation in the interferon response. J Virol 78:10995–11006[CrossRef]
AndoniouC. E.,
van DommelenS. L. H.,
VoigtV.,
AndrewsD. M.,
BrizardG.,
Asselin-PaturelC.,
DelaleT.,
StaceyK. J.,
TrinchieriG.,
Degli-EspostiM. A.2005; Interaction between conventional dendritic cells and natural killer cells is integral to the activation of effective antiviral immunity. Nat Immunol 6:1011–1019[CrossRef]
BoehmeK. W.,
SinghJ.,
PerryS. T.,
ComptonT.2004; Human cytomegalovirus elicits a coordinated cellular antiviral response via envelope glycoprotein B. J Virol 78:1202–1211[CrossRef]
BrinkmannM. M.,
SpoonerE.,
HoebeK.,
BeutlerB.,
PloeghH. L.,
KimY. M.2007; The interaction between the ER membrane protein UNC93B and TLR3, 7, and 9 is crucial for TLR signaling. J Cell Biol 177:265–275[CrossRef]
BrowneE. P.,
ShenkT.2003; Human cytomegalovirus UL83-coded pp65 virion protein inhibits antiviral gene expression in infected cells. Proc Natl Acad Sci U S A 100:11439–11444[CrossRef]
BruneW.,
HengelH.,
KoszinowskiU. H.1999; A mouse model for cytomegalovirus infection. In Current Protocols in Immunology pp. 19.7.1–19.7.3 New York: John Wiley & Sons;
ChildS. J.,
HakkiM.,
De NiroK. L.,
GeballeA. P.2004; Evasion of cellular antiviral responses by human cytomegalovirus TRS1 and IRS1. J Virol 78:197–205[CrossRef]
ChildS. J.,
HansonL. K.,
BrownC. E.,
JanzenD. M.,
GeballeA. P.2006; Double-stranded RNA binding by a heterodimeric complex of murine cytomegalovirus m142 and m143 proteins. J Virol 80:10173–10180[CrossRef]
DarnellJ. E.,
KerrI. M.,
StarkG. R.1994; Jak-Stat pathways and transcriptional activation in response to IFNs and other extracellular signaling proteins. Science 264:1415–1421[CrossRef]
DelaleT.,
PaquinA.,
Asselin-PaturelC.,
DalodM.,
BrizardG.,
BatesE. E. M.,
KastnerP.,
ChanS.,
AkiraS.other authors2005; MyD88-dependent and -independent murine cytomegalovirus sensing for IFN- α release and initiation of immune responses in vivo. J Immunol 175:6723–6732[CrossRef]
GoodbournS.,
ManiatisT.1988; Overlapping positive and negative regulatory domains of the human beta-interferon gene. Proc Natl Acad Sci U S A 85:1447–1451[CrossRef]
HeiseM. T.,
ConnickM.,
VirginH. W.1998; Murine cytomegalovirus inhibits interferon γ -induced antigen presentation to CD4 T cells by macrophages via regulation of expression of major histocompatibility complex class II associated genes. J Exp Med 187:1037–1046[CrossRef]
JarvisM. A.,
BortonJ. A.,
KeechA. M.,
WongJ.,
BrittW. J.,
MagunB. E.,
NelsonJ. A.2006; Human cytomegalovirus attenuates interleukin-1 β and tumor necrosis factor alpha proinflammatory signaling by inhibition of NF- κ B activation. J Virol 80:5588–5598[CrossRef]
KatoH.,
TakeuchiO.,
SatoS.,
YoneyamaM.,
YamamotoM.,
MatsuiK.,
UematsuS.,
JungA.,
KawaiT.other authors2006; Differential roles of MDA5 and RIG-I helicases in the recognition of RNA viruses. Nature 441:101–105[CrossRef]
KrugA.,
FrenchA. R.,
BarchetW.,
FischerJ. A. A.,
DzionekA.,
PingelJ. T.,
OrihuelaM. M.,
AkiraS.,
YokoyamaW. M.,
ColonnaM.2004; TLR-9-dependent recognition of MCMV by IPC and DC generates coordinated cytokine responses that activate antiviral NK cell function. Immunity 21:107–119[CrossRef]
KucharczakJ.,
SimmonsM. J.,
FanY. J.,
GelinasC.2003; To be, or not to be: NF- κ B is the answer – role of Rel/NF- κ B in the regulation of apoptosis. Oncogene 22:8961–8982[CrossRef]
LeeY.,
SohnW. J.,
KimD. S.,
KwonH. J.2004; NF- κ B- and c-Jun-dependent regulation of human cytomegalovirus immediate-early gene enhancer/promoter in response to lipopolysaccharide and bacterial CpG-oligodeoxynucleotides in macrophage cell line RAW 264.7. Eur J Biochem 271:1094–1105[CrossRef]
ManiatisT.,
FalvoJ. V.,
KimT. H.,
KimT. K.,
LinC. H.,
ParekhB. S.,
WatheletM. G.1998; Structure and function of the interferon-beta enhanceosome. Cold Spring Harb Symp Quant Biol 63:609–620[CrossRef]
MathysS.,
SchroederT.,
EllwartJ.,
KoszinowskiU. H.,
MesserleM.,
JustU.2003; Dendritic cells under influence of mouse cytomegalovirus have a physiologic dual role: to initiate and to restrict T cell activation. J Infect Dis 187:988–999[CrossRef]
NogalskiM. T.,
PodduturiJ. P.,
DemerittI. B.,
MilfordL. E.,
YurochkoA. D.2007; The human cytomegalovirus virion possesses an activated casein kinase II that allows for the rapid phosphorylation of the inhibitor of NF- κ B, I κ B α . J Virol 81:5305–5314[CrossRef]
PaulusC.,
KraussS.,
NevelsM.2006; A human cytomegalovirus antagonist of type I IFN-dependent signal transducer and activator of transcription signaling. Proc Natl Acad Sci U S A 103:3840–3845[CrossRef]
PerryA. K.,
ChenG.,
ZhengD. H.,
TangH.,
ChengG. H.2005; The host type I interferon response to viral and bacterial infections. Cell Res 15:407–422[CrossRef]
PooleE.,
KingC. A.,
SinclairJ. H.,
AlcamiA.2006; The UL144 gene product of human cytomegalovirus activates NF- κ B via a TRAF6-dependent mechanism. EMBO J 25:4390–4399[CrossRef]
SambucettiL. C.,
CherringtonJ. M.,
WilkinsonG. W. G.,
MocarskiE. S.1989; NF- κ B activation of the cytomegalovirus enhancer is mediated by a viral transactivator and by T-cell stimulation. EMBO J 8:4251–4258
SatoM.,
HataN.,
AsagiriM.,
NakayaT.,
TaniguchiT.,
TanakaN.1998; Positive feedback regulation of type I IFN genes by the IFN-inducible transcription factor IRF-7. FEBS Lett 441:106–110[CrossRef]
TabetaK.,
GeorgelP.,
JanssenE.,
DuX.,
HoebeK.,
CrozatK.,
MuddS.,
ShamelL.,
SovathS.other authors2004; Toll-like receptors 9 and 3 as essential components of innate immune defense against mouse cytomegalovirus infection. Proc Natl Acad Sci U S A 101:3516–3521[CrossRef]
TakaokaA.,
WangZ.,
ChoiM. K.,
YanaiH.,
NegishiH.,
BanT.,
LuY.,
MiyagishiM.,
KodamaT.other authors2007; DAI (DLM-1/ZBP1) is a cytosolic DNA sensor and an activator of innate immune response. Nature 448:501–505[CrossRef]
ValchanovaR. S.,
Picard-MaureauM.,
BudtM.,
BruneW.2006; Murine cytomegalovirus m142 and m143 are both required to block protein kinase R-mediated shutdown of protein synthesis. J Virol 80:10181–10190[CrossRef]
Van KuppeveldF. J. M.,
JohanssonK. E.,
GalamaJ. M. D.,
KissingJ.,
BolskeG.,
van der LogtJ. T. M.,
MelchersW. J. G.1994; Detection of mycoplasma contamination in cell cultures by a mycoplasma group-specific PCR. Appl Environ Microbiol 60:149–152
WangX.,
SonensheinG. E.2005; Induction of the RelB NF- κ B subunit by the cytomegalovirus IE1 protein is mediated via jun kinase and c-Jun/Fra-2 AP-1 complexes. J Virol 79:95–105[CrossRef]
YurochkoA. D.,
KowalikT. F.,
HuongS. M.,
HuangE. S.1995; Human cytomegalovirus up-regulates NF-kappaB activity by transactivating the NF-kappaB p105/p50 and p65 promoters. J Virol 69:5391–5400
YurochkoA. D.,
HwangE. S.,
RasmussenL.,
KeayS.,
PereiraL.,
HuangE. S.1997; The human cytomegalovirus UL55 (gB) and UL75 (gH) glycoprotein ligands initiate the rapid activation of Sp1 and NF-kappaB during infection. J Virol 71:5051–5059
ZimmermannA.,
TrillingM.,
WagnerM.,
WilbornM.,
BubicI.,
JonjicS.,
KoszinowskiU.,
HengelH.2005; A cytomegaloviral protein reveals a dual role for STAT2 in IFN- γ signaling and antiviral responses. J Exp Med 201:1543–1553[CrossRef]