Distinct IL-1α-responsive enhancers promote acute and coordinated changes in chromatin topology in a hierarchical manner
How cytokine-driven changes in chromatin topology are converted into gene regulatory circuits during inflammation still remains unclear. Here, we show that interleukin (IL)-1α induces acute and widespread changes in chromatin accessibility via the TAK1 kinase and NF-κB at regions that are highly enriched for inflammatory disease-relevant SNPs. Two enhancers in the extended chemokine locus on human chromosome 4 regulate the IL-1α-inducible IL8 and CXCL1-3 genes. Both enhancers engage in dynamic spatial interactions with gene promoters in an IL-1α/TAK1-inducible manner. Microdeletions of p65-binding sites in either of the two enhancers impair NF-κB recruitment, suppress activation and biallelic transcription of the IL8/CXCL2 genes, and reshuffle higher-order chromatin interactions as judged by i4C interactome profiles. Notably, these findings support a dominant role of the IL8 “master” enhancer in the regulation of sustained IL-1α signaling, as well as for IL-8 and IL-6 secretion. CRISPR-guided transactivation of the IL8 locus or cross-TAD regulation by TNFα-responsive enhancers in a different model locus supports the existence of complex enhancer hierarchies in response to cytokine stimulation that prime and orchestrate proinflammatory chromatin responses downstream of NF-κB.
|Keywords||chromatin topology, IL-8, interleukin-1, NF-κB, tumor necrosis factor-α|
|Persistent URL||dx.doi.org/10.15252/embj.2019101533, hdl.handle.net/1765/121475|
Weiterer, S.-S. (Sinah-Sophia), Meier-Soelch, J. (Johanna), Georgomanolis, T. (Theodore), Mizi, A. (Athanasia), Beyerlein, A. (Anna), Weiser, H. (Hendrik), … Kracht, M. (Michael). (2019). Distinct IL-1α-responsive enhancers promote acute and coordinated changes in chromatin topology in a hierarchical manner. EMBO Journal. doi:10.15252/embj.2019101533