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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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Recruitment of HDAC3 to IFN-A gene promoters during virus infection.(A) Relative expression levels of HDAC3 were determined in Sendai virus-infected Namalwa cells by RT-QPCR as described in Figure 1. HDAC3 protein levels were analyzed in whole cell extracts prepared from Sendai virus-infected Namalwa B cells by Western blotting using HDAC3 and actin antisera. (B) Recruitment of HDAC3 and HDAC1 to the IFN-A2, A14 and A1 gene promoters was determined in Namalwa B cells infected by Sendai virus for 4 to 16 h by quantitative ChIP assays as described in Figure 2. Anti-rabbit IgG was used to determine non-specific binding.
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pone-0038336-g004: Recruitment of HDAC3 to IFN-A gene promoters during virus infection.(A) Relative expression levels of HDAC3 were determined in Sendai virus-infected Namalwa cells by RT-QPCR as described in Figure 1. HDAC3 protein levels were analyzed in whole cell extracts prepared from Sendai virus-infected Namalwa B cells by Western blotting using HDAC3 and actin antisera. (B) Recruitment of HDAC3 and HDAC1 to the IFN-A2, A14 and A1 gene promoters was determined in Namalwa B cells infected by Sendai virus for 4 to 16 h by quantitative ChIP assays as described in Figure 2. Anti-rabbit IgG was used to determine non-specific binding.

Mentions: Several studies have implicated HDAC activities in reversal of histone acetylation and attenuation of a transcriptional response [62], [63]. We observed that infection of Namalwa cells by SeV resulted in a strong and transient increase in HDAC3 mRNA and protein levels at 9–16 h p.i (Fig. 4A). In Western blots, in addition to the 50-kDa form of HDAC3, we detected a slower migrating complex reacting with HDAC3 antibodies that might correspond to a post-translationally modified form of HDAC3 that appears during virus infection. Because virus infection stimulated HDAC3 expression, we tested whether HDAC3 was recruited to IFN-A gene promoters during virus infection. Interestingly, HDAC3 recruitment to different IFN-A gene promoters was observed at 12–16 h p.i, with levels ranging from 2 to 3% of the input DNA and providing a 3- to 6-fold enrichment (p<0.01), whereas other HDACs including HDAC1 were not recruited (Fig. 4Band data not shown). These results indicated that the inhibition of H3K9/K14 acetylation at 14–16 h p.i correlated with HDAC3 recruitment to IFN-A promoters.


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)

Recruitment of HDAC3 to IFN-A gene promoters during virus infection.(A) Relative expression levels of HDAC3 were determined in Sendai virus-infected Namalwa cells by RT-QPCR as described in Figure 1. HDAC3 protein levels were analyzed in whole cell extracts prepared from Sendai virus-infected Namalwa B cells by Western blotting using HDAC3 and actin antisera. (B) Recruitment of HDAC3 and HDAC1 to the IFN-A2, A14 and A1 gene promoters was determined in Namalwa B cells infected by Sendai virus for 4 to 16 h by quantitative ChIP assays as described in Figure 2. Anti-rabbit IgG was used to determine non-specific binding.
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Related In: Results  -  Collection

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getmorefigures.php?uid=PMC3369917&req=5

pone-0038336-g004: Recruitment of HDAC3 to IFN-A gene promoters during virus infection.(A) Relative expression levels of HDAC3 were determined in Sendai virus-infected Namalwa cells by RT-QPCR as described in Figure 1. HDAC3 protein levels were analyzed in whole cell extracts prepared from Sendai virus-infected Namalwa B cells by Western blotting using HDAC3 and actin antisera. (B) Recruitment of HDAC3 and HDAC1 to the IFN-A2, A14 and A1 gene promoters was determined in Namalwa B cells infected by Sendai virus for 4 to 16 h by quantitative ChIP assays as described in Figure 2. Anti-rabbit IgG was used to determine non-specific binding.
Mentions: Several studies have implicated HDAC activities in reversal of histone acetylation and attenuation of a transcriptional response [62], [63]. We observed that infection of Namalwa cells by SeV resulted in a strong and transient increase in HDAC3 mRNA and protein levels at 9–16 h p.i (Fig. 4A). In Western blots, in addition to the 50-kDa form of HDAC3, we detected a slower migrating complex reacting with HDAC3 antibodies that might correspond to a post-translationally modified form of HDAC3 that appears during virus infection. Because virus infection stimulated HDAC3 expression, we tested whether HDAC3 was recruited to IFN-A gene promoters during virus infection. Interestingly, HDAC3 recruitment to different IFN-A gene promoters was observed at 12–16 h p.i, with levels ranging from 2 to 3% of the input DNA and providing a 3- to 6-fold enrichment (p<0.01), whereas other HDACs including HDAC1 were not recruited (Fig. 4Band data not shown). These results indicated that the inhibition of H3K9/K14 acetylation at 14–16 h p.i correlated with HDAC3 recruitment to IFN-A promoters.

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