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Neddylation is required for herpes simplex virus type I (HSV-1)-induced early phase interferon-beta production

View Article: PubMed Central - PubMed

ABSTRACT

Type I interferons such as interferon-beta (IFN-β) play essential roles in the host innate immune response to herpes simplex virus type I (HSV-1) infection. The transcription of type I interferon genes is controlled by nuclear factor-κB (NF-κB) and interferon regulatory factor (IRF) family members including IRF3. NF-κB activation depends on the phosphorylation of inhibitor of κB (IκB), which triggers its ubiqitination and degradation. It has been reported that neddylation inhibition by a pharmacological agent MLN4924 potently suppresses lipopolysaccharide (LPS)-induced proinflammatory cytokine production with the accumulation of phosphorylated IκBα. However, the role of neddylation in type I interferon expression remains unknown. Here, we report that neddylation inhibition with MLN4924 or upon UBA3 deficiency led to accumulation of phosphorylated IκBα, impaired IκBα degradation, and impaired NF-κB nuclear translocation in the early phase of HSV-1 infection even though phosphorylation and nuclear translocation of IRF3 were not affected. The blockade of NF-κB nuclear translocation by neddylation inhibition becomes less efficient at the later time points of HSV-1 infection. Consequently, HSV-1-induced early phase IFN-β production significantly decreased upon MLN4924 treatment and UBA3 deficiency. NF-κB inhibitor JSH-23 mimicked the effects of neddylation inhibition in the early phase of HSV-1 infection. Moreover, the effects of neddylation inhibition on HSV-1-induced early phase IFN-β production diminished in the presence of NF-κB inhibitor JSH-23. Thus, neddylation contributes to HSV-1-induced early phase IFN-β production through, at least partially, promoting NF-κB activation.

No MeSH data available.


HSV-1-induced early phase NF-κB activation is impaired upon UBA3 deficiency. BMMs from UBA3F/F and UBA3ΔMye mice were infected with HSV-1 for 0, 1, 4 h. (a) Cell lysates were harvested and subjected to immunoblotting analysis with the indicated antibodies. (b) The subcellular localization of p65 subunit of NF-κB (red) was revealed by indirect immunofluorescence staining with a p65-specific antibody. Nuclei were counterstained for DNA by DAPI (blue).
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fig3: HSV-1-induced early phase NF-κB activation is impaired upon UBA3 deficiency. BMMs from UBA3F/F and UBA3ΔMye mice were infected with HSV-1 for 0, 1, 4 h. (a) Cell lysates were harvested and subjected to immunoblotting analysis with the indicated antibodies. (b) The subcellular localization of p65 subunit of NF-κB (red) was revealed by indirect immunofluorescence staining with a p65-specific antibody. Nuclei were counterstained for DNA by DAPI (blue).

Mentions: Our previous data suggest that neddylation inhibition with MLN4924 leads to impaired NF-κB activation in the early phase of HSV-1 infection without disturbing the upstream molecular events. To confirm the defective early phase NF-κB activation upon neddylation inhibition, we cultured BMMs from mice homozygous for a UBA3 conditional allele (UBA3F/F) and UBA3F/F; Lyz2-Cre (named as UBA3Δmye) mice. BMMs were infected with HSV-1 for 0, 1, and 4 h, and subjected to immunoblotting analysis with specific antibodies. As shown in Figure 3a, UBA3 deficiency significantly abrogated the neddylation of Cullins. Furthermore, HSV-1-induced IκBα degradation was delayed upon UBA3 deficiency, which was associated with significant accumulation of phosphorylated IκBα (Figure 3a). Consistently, indirect immunofluorescence microscopy revealed that HSV-1-induced nuclear translocation of p65 subunit of NF-κB was impaired upon UBA3 deficiency (Figure 3b). These data confirm that neddylation inhibition leads to impaired NF-κB activation in the early phase of HSV-1 infection.


Neddylation is required for herpes simplex virus type I (HSV-1)-induced early phase interferon-beta production
HSV-1-induced early phase NF-κB activation is impaired upon UBA3 deficiency. BMMs from UBA3F/F and UBA3ΔMye mice were infected with HSV-1 for 0, 1, 4 h. (a) Cell lysates were harvested and subjected to immunoblotting analysis with the indicated antibodies. (b) The subcellular localization of p65 subunit of NF-κB (red) was revealed by indirect immunofluorescence staining with a p65-specific antibody. Nuclei were counterstained for DNA by DAPI (blue).
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Related In: Results  -  Collection

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fig3: HSV-1-induced early phase NF-κB activation is impaired upon UBA3 deficiency. BMMs from UBA3F/F and UBA3ΔMye mice were infected with HSV-1 for 0, 1, 4 h. (a) Cell lysates were harvested and subjected to immunoblotting analysis with the indicated antibodies. (b) The subcellular localization of p65 subunit of NF-κB (red) was revealed by indirect immunofluorescence staining with a p65-specific antibody. Nuclei were counterstained for DNA by DAPI (blue).
Mentions: Our previous data suggest that neddylation inhibition with MLN4924 leads to impaired NF-κB activation in the early phase of HSV-1 infection without disturbing the upstream molecular events. To confirm the defective early phase NF-κB activation upon neddylation inhibition, we cultured BMMs from mice homozygous for a UBA3 conditional allele (UBA3F/F) and UBA3F/F; Lyz2-Cre (named as UBA3Δmye) mice. BMMs were infected with HSV-1 for 0, 1, and 4 h, and subjected to immunoblotting analysis with specific antibodies. As shown in Figure 3a, UBA3 deficiency significantly abrogated the neddylation of Cullins. Furthermore, HSV-1-induced IκBα degradation was delayed upon UBA3 deficiency, which was associated with significant accumulation of phosphorylated IκBα (Figure 3a). Consistently, indirect immunofluorescence microscopy revealed that HSV-1-induced nuclear translocation of p65 subunit of NF-κB was impaired upon UBA3 deficiency (Figure 3b). These data confirm that neddylation inhibition leads to impaired NF-κB activation in the early phase of HSV-1 infection.

View Article: PubMed Central - PubMed

ABSTRACT

Type I interferons such as interferon-beta (IFN-β) play essential roles in the host innate immune response to herpes simplex virus type I (HSV-1) infection. The transcription of type I interferon genes is controlled by nuclear factor-κB (NF-κB) and interferon regulatory factor (IRF) family members including IRF3. NF-κB activation depends on the phosphorylation of inhibitor of κB (IκB), which triggers its ubiqitination and degradation. It has been reported that neddylation inhibition by a pharmacological agent MLN4924 potently suppresses lipopolysaccharide (LPS)-induced proinflammatory cytokine production with the accumulation of phosphorylated IκBα. However, the role of neddylation in type I interferon expression remains unknown. Here, we report that neddylation inhibition with MLN4924 or upon UBA3 deficiency led to accumulation of phosphorylated IκBα, impaired IκBα degradation, and impaired NF-κB nuclear translocation in the early phase of HSV-1 infection even though phosphorylation and nuclear translocation of IRF3 were not affected. The blockade of NF-κB nuclear translocation by neddylation inhibition becomes less efficient at the later time points of HSV-1 infection. Consequently, HSV-1-induced early phase IFN-β production significantly decreased upon MLN4924 treatment and UBA3 deficiency. NF-κB inhibitor JSH-23 mimicked the effects of neddylation inhibition in the early phase of HSV-1 infection. Moreover, the effects of neddylation inhibition on HSV-1-induced early phase IFN-β production diminished in the presence of NF-κB inhibitor JSH-23. Thus, neddylation contributes to HSV-1-induced early phase IFN-β production through, at least partially, promoting NF-κB activation.

No MeSH data available.