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Recruitment of histone deacetylase 3 to the interferon-A gene promoters attenuates interferon expression.

Génin P, Lin R, Hiscott J, Civas A - PLoS ONE (2012)

Bottom Line: Analysis of chromatin-protein association by Chip-QPCR demonstrated that recruitment of interferon regulatory factor (IRF)3 and IRF7, as well as TBP correlated with enhanced histone H3K9 and H3K14 acetylation, whereas recruitment of HDAC3 correlated with inhibition of histone H3K9/K14 acetylation, removal of IRF7 and TATA-binding protein (TBP) from IFN-A promoters and inhibition of virus-induced IFN-A gene transcription.Additionally, HDAC3 overexpression reduced, and HDAC3 depletion by siRNA enhanced IFN-A gene expression.Furthermore, activation of IRF7 enhanced histone H3K9/K14 acetylation and IFN-A gene expression, whereas activation of both IRF7 and IRF3 led to recruitment of HDAC3 to the IFN-A gene promoters, resulting in impaired histone H3K9 acetylation and attenuation of IFN-A gene transcription.

View Article: PubMed Central - PubMed

Affiliation: Centre National de la Recherche Scientifique-FRE3235, Paris Descartes University, Paris, France.

ABSTRACT

Background: Induction of Type I Interferon (IFN) genes constitutes an essential step leading to innate immune responses during virus infection. Sendai virus (SeV) infection of B lymphoid Namalwa cells transiently induces the transcriptional expression of multiple IFN-A genes. Although transcriptional activation of IFN-A genes has been extensively studied, the mechanism responsible for the attenuation of their expression remains to be determined.

Principal findings: In this study, we demonstrate that virus infection of Namalwa cells induces transient recruitment of HDAC3 (histone deacetylase 3) to IFN-A promoters. Analysis of chromatin-protein association by Chip-QPCR demonstrated that recruitment of interferon regulatory factor (IRF)3 and IRF7, as well as TBP correlated with enhanced histone H3K9 and H3K14 acetylation, whereas recruitment of HDAC3 correlated with inhibition of histone H3K9/K14 acetylation, removal of IRF7 and TATA-binding protein (TBP) from IFN-A promoters and inhibition of virus-induced IFN-A gene transcription. Additionally, HDAC3 overexpression reduced, and HDAC3 depletion by siRNA enhanced IFN-A gene expression. Furthermore, activation of IRF7 enhanced histone H3K9/K14 acetylation and IFN-A gene expression, whereas activation of both IRF7 and IRF3 led to recruitment of HDAC3 to the IFN-A gene promoters, resulting in impaired histone H3K9 acetylation and attenuation of IFN-A gene transcription.

Conclusion: Altogether these data indicate that reversal of histone H3K9/K14 acetylation by HDAC3 is required for attenuation of IFN-A gene transcription during viral infection.

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Regulation of histone H3 acetylation associated with the IFN-A2 gene promoter.(A) IFN-A2 expression was determined in HEK293-TLR3 cells co-expressing IKKε and IRF7 alone or together with IRF3. Cells were collected for RT-QPCR analysis at the indicated times (in hours) after transfection. (B) Acetylated histone H3K9, acetylated H3K14 and histone H3, as well as recruitment of IRF3, IRF7 and HDAC3 associated with the IFN-A2 gene promoter were determined by quantitative ChIP assays as described in Materials and Methods. Anti-rabbit IgG was used to determine non-specific binding.
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pone-0038336-g005: Regulation of histone H3 acetylation associated with the IFN-A2 gene promoter.(A) IFN-A2 expression was determined in HEK293-TLR3 cells co-expressing IKKε and IRF7 alone or together with IRF3. Cells were collected for RT-QPCR analysis at the indicated times (in hours) after transfection. (B) Acetylated histone H3K9, acetylated H3K14 and histone H3, as well as recruitment of IRF3, IRF7 and HDAC3 associated with the IFN-A2 gene promoter were determined by quantitative ChIP assays as described in Materials and Methods. Anti-rabbit IgG was used to determine non-specific binding.

Mentions: To investigate further the involvement of HDAC3 in inhibition of IFN-A transcription, via H3K9 and H3K14 deacetylation, transient expression studies were performed in HEK293-TLR3 cells co-expressing IRF7 in the presence of IKKε. In this model, active IFN-A transcription correlated with recruitment of IRF7 and histone H3 acetylation, whereas no HDAC3 recruitment was observed (Fig. 5A-B). We have shown that IRF3 cooperates with IRF7 when low amounts of both factors are expressed, but also can act as a repressor of IRF7-mediated transcription when expressed at higher amounts compared to IRF7 [34]. Interestingly, when high levels of both IRF3 and IRF7 were activated in the presence of IKKε, we observed significant levels of HDAC3 recruitment (2.5 to 3.7% of input, with p<0.01) that correlated with a decrease in H3K9 and H3K14 acetylation and an impaired IFN-A2 gene expression (Fig. 5A-B). In this experiment, a 5- to 20-fold reduction in H3K9 acetylation and 2-fold reduction in H3K14 acetylation was observed compared to H3 acetylation levels in cells expressing IKKε and IRF7.


Recruitment of histone deacetylase 3 to the interferon-A gene promoters attenuates interferon expression.

Génin P, Lin R, Hiscott J, Civas A - PLoS ONE (2012)

Regulation of histone H3 acetylation associated with the IFN-A2 gene promoter.(A) IFN-A2 expression was determined in HEK293-TLR3 cells co-expressing IKKε and IRF7 alone or together with IRF3. Cells were collected for RT-QPCR analysis at the indicated times (in hours) after transfection. (B) Acetylated histone H3K9, acetylated H3K14 and histone H3, as well as recruitment of IRF3, IRF7 and HDAC3 associated with the IFN-A2 gene promoter were determined by quantitative ChIP assays as described in Materials and Methods. Anti-rabbit IgG was used to determine non-specific binding.
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC3369917&req=5

pone-0038336-g005: Regulation of histone H3 acetylation associated with the IFN-A2 gene promoter.(A) IFN-A2 expression was determined in HEK293-TLR3 cells co-expressing IKKε and IRF7 alone or together with IRF3. Cells were collected for RT-QPCR analysis at the indicated times (in hours) after transfection. (B) Acetylated histone H3K9, acetylated H3K14 and histone H3, as well as recruitment of IRF3, IRF7 and HDAC3 associated with the IFN-A2 gene promoter were determined by quantitative ChIP assays as described in Materials and Methods. Anti-rabbit IgG was used to determine non-specific binding.
Mentions: To investigate further the involvement of HDAC3 in inhibition of IFN-A transcription, via H3K9 and H3K14 deacetylation, transient expression studies were performed in HEK293-TLR3 cells co-expressing IRF7 in the presence of IKKε. In this model, active IFN-A transcription correlated with recruitment of IRF7 and histone H3 acetylation, whereas no HDAC3 recruitment was observed (Fig. 5A-B). We have shown that IRF3 cooperates with IRF7 when low amounts of both factors are expressed, but also can act as a repressor of IRF7-mediated transcription when expressed at higher amounts compared to IRF7 [34]. Interestingly, when high levels of both IRF3 and IRF7 were activated in the presence of IKKε, we observed significant levels of HDAC3 recruitment (2.5 to 3.7% of input, with p<0.01) that correlated with a decrease in H3K9 and H3K14 acetylation and an impaired IFN-A2 gene expression (Fig. 5A-B). In this experiment, a 5- to 20-fold reduction in H3K9 acetylation and 2-fold reduction in H3K14 acetylation was observed compared to H3 acetylation levels in cells expressing IKKε and IRF7.

Bottom Line: Analysis of chromatin-protein association by Chip-QPCR demonstrated that recruitment of interferon regulatory factor (IRF)3 and IRF7, as well as TBP correlated with enhanced histone H3K9 and H3K14 acetylation, whereas recruitment of HDAC3 correlated with inhibition of histone H3K9/K14 acetylation, removal of IRF7 and TATA-binding protein (TBP) from IFN-A promoters and inhibition of virus-induced IFN-A gene transcription.Additionally, HDAC3 overexpression reduced, and HDAC3 depletion by siRNA enhanced IFN-A gene expression.Furthermore, activation of IRF7 enhanced histone H3K9/K14 acetylation and IFN-A gene expression, whereas activation of both IRF7 and IRF3 led to recruitment of HDAC3 to the IFN-A gene promoters, resulting in impaired histone H3K9 acetylation and attenuation of IFN-A gene transcription.

View Article: PubMed Central - PubMed

Affiliation: Centre National de la Recherche Scientifique-FRE3235, Paris Descartes University, Paris, France.

ABSTRACT

Background: Induction of Type I Interferon (IFN) genes constitutes an essential step leading to innate immune responses during virus infection. Sendai virus (SeV) infection of B lymphoid Namalwa cells transiently induces the transcriptional expression of multiple IFN-A genes. Although transcriptional activation of IFN-A genes has been extensively studied, the mechanism responsible for the attenuation of their expression remains to be determined.

Principal findings: In this study, we demonstrate that virus infection of Namalwa cells induces transient recruitment of HDAC3 (histone deacetylase 3) to IFN-A promoters. Analysis of chromatin-protein association by Chip-QPCR demonstrated that recruitment of interferon regulatory factor (IRF)3 and IRF7, as well as TBP correlated with enhanced histone H3K9 and H3K14 acetylation, whereas recruitment of HDAC3 correlated with inhibition of histone H3K9/K14 acetylation, removal of IRF7 and TATA-binding protein (TBP) from IFN-A promoters and inhibition of virus-induced IFN-A gene transcription. Additionally, HDAC3 overexpression reduced, and HDAC3 depletion by siRNA enhanced IFN-A gene expression. Furthermore, activation of IRF7 enhanced histone H3K9/K14 acetylation and IFN-A gene expression, whereas activation of both IRF7 and IRF3 led to recruitment of HDAC3 to the IFN-A gene promoters, resulting in impaired histone H3K9 acetylation and attenuation of IFN-A gene transcription.

Conclusion: Altogether these data indicate that reversal of histone H3K9/K14 acetylation by HDAC3 is required for attenuation of IFN-A gene transcription during viral infection.

Show MeSH
Related in: MedlinePlus