Acetylation of Stat1 modulates NF-kappaB activity

Georg-Speyer-Haus, D-60596 Frankfurt, Germany.
Genes & Development (Impact Factor: 10.8). 03/2006; 20(4):473-85. DOI: 10.1101/gad.364306
Source: PubMed


Acetylation of signaling molecules can lead to apoptosis or differentiation of carcinoma cells. The molecular mechanisms underlying these processes and the biological role of enzymes mediating the transfer or removal of an acetyl-group are currently under intense investigation. Our study shows that Stat1 is an acetylated protein. Stat1 acetylation depends on the balance between Stat1-associated histone deacetylases (HDACs) and histone acetyltransferases (HATs) such as CBP. Remarkably both inhibitors of HDACs and the cytokine interferon alpha alter this equilibrium and induce Stat1 acetylation. The analysis of Stat1 mutants reveals Lys 410 and Lys 413 as acetylation sites. Experiments with Stat1 mutants mimicking either constitutively acetylated or nonacetylated states show that only acetylated Stat1 is able to interact with NF-kappaB p65. As a consequence, p65 DNA binding, nuclear localization, and expression of anti-apoptotic NF-kappaB target genes decrease. These findings show how the acetylation of Stat1 regulates NF-kappaB activity and thus ultimately apoptosis.

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Available from: Thorsten Heinzel, Apr 18, 2014
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    • "Furthermore, while the interactions with some transcription factors increases the DNA binding of NFκB complexes to target genes, as is observed with STAT3 (Nadiminty et al., 2006), interactions with similar factors (i.e. STAT1) can have the opposite effect, and impair NFκB DNA binding (Kramer et al., 2006). "
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    • "Specifically acetylation on lysine residues 122 and 123 by p300 and PCAF (p300/CBP-associated factor) was shown to reduce the binding of NF-κB to κB promoter regions and facilitate the IκBα-dependent nuclear export (Kiernan et al., 2003). Moreover, the acetylation of Signal Transducers and Activators of Transcription 1 (STAT1) results in the binding of STAT1 to NF-κB and thus reduces NF-κB signaling (Kramer et al., 2006). "
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