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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 IRF3 activation remains unchanged upon UBA3 deficiency. BMMs from UBA3F/F and UBA3ΔMye mice were infected with HSV-1 for 0, 1, and 4 h. (a) Cell lysates were harvested and subjected to immunoblotting analysis with the indicated antibodies. (b) The subcellular localization of IRF3 (red) was revealed by indirect immunofluorescence staining with an IRF3-specific antibody. Nuclei were counterstained for DNA by DAPI (blue).
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fig4: HSV-1-induced early phase IRF3 activation remains unchanged upon UBA3 deficiency. BMMs from UBA3F/F and UBA3ΔMye mice were infected with HSV-1 for 0, 1, and 4 h. (a) Cell lysates were harvested and subjected to immunoblotting analysis with the indicated antibodies. (b) The subcellular localization of IRF3 (red) was revealed by indirect immunofluorescence staining with an IRF3-specific antibody. Nuclei were counterstained for DNA by DAPI (blue).

Mentions: Next, we examined whether UBA3 deficiency affects IRF3 activation in the early phase of HSV-1 infection. Immunoblotting analysis revealed that HSV-1-induced IRF3 phosphorylation remained unchanged upon UBA3 deficiency (Figure 4a). Moreover, indirect immunofluorescence microscopy revealed that HSV-1-induced nuclear translocation of IRF3 was not affected (Figure 4b). These data confirm that neddylation inhibition does not affect early phase IRF3 activation in response to 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 IRF3 activation remains unchanged upon UBA3 deficiency. BMMs from UBA3F/F and UBA3ΔMye mice were infected with HSV-1 for 0, 1, and 4 h. (a) Cell lysates were harvested and subjected to immunoblotting analysis with the indicated antibodies. (b) The subcellular localization of IRF3 (red) was revealed by indirect immunofluorescence staining with an IRF3-specific antibody. Nuclei were counterstained for DNA by DAPI (blue).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC5037273&req=5

fig4: HSV-1-induced early phase IRF3 activation remains unchanged upon UBA3 deficiency. BMMs from UBA3F/F and UBA3ΔMye mice were infected with HSV-1 for 0, 1, and 4 h. (a) Cell lysates were harvested and subjected to immunoblotting analysis with the indicated antibodies. (b) The subcellular localization of IRF3 (red) was revealed by indirect immunofluorescence staining with an IRF3-specific antibody. Nuclei were counterstained for DNA by DAPI (blue).
Mentions: Next, we examined whether UBA3 deficiency affects IRF3 activation in the early phase of HSV-1 infection. Immunoblotting analysis revealed that HSV-1-induced IRF3 phosphorylation remained unchanged upon UBA3 deficiency (Figure 4a). Moreover, indirect immunofluorescence microscopy revealed that HSV-1-induced nuclear translocation of IRF3 was not affected (Figure 4b). These data confirm that neddylation inhibition does not affect early phase IRF3 activation in response to 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.