Revision as of 11:00, 26 October 2020

Interleukin-6 Promoter (IL-6 P)

Usage and Biology

The human interleukin-6 promoter originally controls the expression of the cytokine Il-6 that is involved in the regulation of the acute-phase response to injury and infection but also other processes like hematopoiesis and embryonal development (Heinrich el al. 2003). The regulation of transcription exerted by the IL-6 promoter is mainly controlled by several cis-acting response elements present within the promoter region including binding motifs for NF-κB, NF-IL6, CREB, C/EBP, AP-1 and AP-2 (Xiao et al. 2004, Beetz et al. 2000). The regulation of the IL-6 promoter depends on the cell type and the stimulus. This means that different transcription factors are needed under different conditions. In our study we used LPS to induce IL-6 promoter activation. In this case the transcription factors NF-κB and AP1 play important roles (Xiao et al. 2004, Liu et al. 2018). The activation of the promoter is achieved by the cooperative binding of NF-κB and c-Jun (AP-1) (Xiao et al. 2004). AP-1- and NF-κB-translocation to the nucleus is triggered downstream of Toll like receptor (TLR) signaling cascades involving TRIF, MyD88, RIPK1 and TAK1. Toll like receptors are activated by a variety of pathogen-associated molecular patterns (Kawai and Akira 2007).

In our study we used it as a LPS sensor for our inflammatory toxin sensor. After treatment of transfected HeLa cells with LPS a significant and long-lasting upregulation of the promoter activity was observed. However, it does not match the Biobrick assembly standard requirements. Therefore, we generated a mutant that is Biobrick compatible (BBa_K3338005) but unfortunately does not show LPS sensitivity.

Sequence and Features

References

Beetz, A., Peter, R. U., Oppel, T., Kaffenberger, W., Rupec, R. A., Meyer, M., van Beuningen, D., Kind, P., & Messer, G. (2000). NF-kappaB and AP-1 are responsible for inducibility of the IL-6 promoter by ionizing radiation in HeLa cells. International journal of radiation biology, 76(11), 1443–1453.

Heinrich, P. C., Behrmann, I., Haan, S., Hermanns, H. M., Müller-Newen, G., & Schaper, F. (2003). Principles of interleukin (IL)-6-type cytokine signalling and its regulation. The Biochemical journal, 374(Pt 1), 1–20.

Kawai, T., & Akira, S. (2007). Signaling to NF-kappaB by Toll-like receptors. Trends in molecular medicine, 13(11), 460–469.

Liu, X., Yin, S., Chen, Y., Wu, Y., Zheng, W., Dong, H., Bai, Y., Qin, Y., Li, J., Feng, S., & Zhao, P. (2018). LPS‑induced proinflammatory cytokine expression in human airway epithelial cells and macrophages via NF‑κB, STAT3 or AP‑1 activation. Molecular medicine reports, 17(4), 5484–5491.

Xiao, W., Hodge, D. R., Wang, L., Yang, X., Zhang, X., & Farrar, W. L. (2004). NF-kappaB activates IL-6 expression through cooperation with c-Jun and IL6-AP1 site, but is independent of its IL6-NFkappaB regulatory site in autocrine human multiple myeloma cells. Cancer biology & therapy, 3(10), 1007–1017.