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Figure

Figure 11: Activation of NF-κB

Ligand binding to different cell membrane receptors (Toll-like/IL-1, TNF) activates intracellular signal transduction molecules such as the receptor associated protein kinases Interleukin 1 Receptor-Associated Kinase (IRAK) and TNF receptor-associated factor (TRAF) and then the cytosolic proteinkinase NF-κB-inducing Kinase (NIK). This kinase phophorlyses IkB Kinase (IKK), which in turn activates IκB. Phosphorylsed IκB binds to Ubiquitin, which transfers the NF-κB/IκB-complex to cellular proteasomes for degradation. Following Abspaltung of IκB within the proteasome, NF-κB can be transferred into the nucleus and promote the transcription of genes with appropriate responsive elements. Reaktive oxygen species activate stress-activated-protein-kinases, which in turn activate auxiliary proteins such as CBP and p300. This enhances the NF-κB binding to its responsive elements.