TY - JOUR
T1 - Suppression of steady-state, but not stimulus-induced NF-κB activity inhibits alphavirus-induced apoptosis
AU - Lin, Kuo I.
AU - DiDonato, Joseph A.
AU - Hoffmann, Alexander
AU - Hardwick, J. Marie
AU - Ratan, Rajiv R.
PY - 1998/6/29
Y1 - 1998/6/29
N2 - Recent studies have established cell type-specific, proapoptotic, or antiapoptotic functions for the transcription factor NF-κB. In each of these studies, inhibitors of NF-κB activity have been present before the apoptotic stimulus, and so the role of stimulus-induced NF-κB activation in enhancing or inhibiting survival could not be directly assessed. Sindbis virus, an alphavirus, induces NF-κB activation and apoptosis in cultured cell lines. To address whether Sindbis virus-induced NF-κB activation is required for apoptosis, we used a chimeric Sindbis virus that expresses a superrepressor of NF-κB activity. Complete suppression of virus-induced NF-κB activity neither prevents nor potentiates Sindbis virus-induced apoptosis. In contrast, inhibition of NF-κB activity before infection inhibits Sindbis virus-induced apoptosis. Our results demonstrate that suppression of steady- state, but not stimulus-induced NF-κB activity, regulates expression of gene products required for Sindbis virus-induced death. Furthermore, we show that in the same cell line, NF-κB can be proapoptotic or antiapoptotic depending on the death stimulus. We propose that the role of NF-κB in regulating apoptosis is determined by the death stimulus and by the timing of modulating NF-κB activity relative to the death stimulus.
AB - Recent studies have established cell type-specific, proapoptotic, or antiapoptotic functions for the transcription factor NF-κB. In each of these studies, inhibitors of NF-κB activity have been present before the apoptotic stimulus, and so the role of stimulus-induced NF-κB activation in enhancing or inhibiting survival could not be directly assessed. Sindbis virus, an alphavirus, induces NF-κB activation and apoptosis in cultured cell lines. To address whether Sindbis virus-induced NF-κB activation is required for apoptosis, we used a chimeric Sindbis virus that expresses a superrepressor of NF-κB activity. Complete suppression of virus-induced NF-κB activity neither prevents nor potentiates Sindbis virus-induced apoptosis. In contrast, inhibition of NF-κB activity before infection inhibits Sindbis virus-induced apoptosis. Our results demonstrate that suppression of steady- state, but not stimulus-induced NF-κB activity, regulates expression of gene products required for Sindbis virus-induced death. Furthermore, we show that in the same cell line, NF-κB can be proapoptotic or antiapoptotic depending on the death stimulus. We propose that the role of NF-κB in regulating apoptosis is determined by the death stimulus and by the timing of modulating NF-κB activity relative to the death stimulus.
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U2 - 10.1083/jcb.141.7.1479
DO - 10.1083/jcb.141.7.1479
M3 - Article
C2 - 9647642
AN - SCOPUS:0032577979
SN - 0021-9525
VL - 141
SP - 1479
EP - 1487
JO - Journal of Cell Biology
JF - Journal of Cell Biology
IS - 7
ER -