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Nf-kappab
Synonym(s)
NFkappaB; NFkappaB signaling pathway
DefinitionThis section has been translated automatically.
Specific transcription factor that occurs ubiquitously in all cell types and tissues. By binding to certain regulatory sections of DNA, it can influence the transcription of dependent genes. NF-kappaB has numerous target genes and mediates a broad range of effects (NFkappaB signalling pathway). NF-kappaB is of great importance for the regulation of the immune response, cell proliferation and apoptosis. The activation of NF-kappaB is considered important for the development of inflammation, e.g. in the inflammatory induction of dermatitis solaris.
ClassificationThis section has been translated automatically.
- 5 subunits of NF-kappaB are currently known (alternative name in brackets):
- NF-κB1 (p50 or p105)
- NF-κB2 (p52 or p100)
- RelA (p65)
- RelB
- c-Rel.
General informationThis section has been translated automatically.
In some cells, NF-kappaB is always present in the nucleus and thus active without the influence of external stimuli. This concerns for example B-lymphocytes and dendritic cells. In most other cells, however, NF-kappaB is inactive in the cytoplasm and therefore has no access to the DNA located in the nucleus. This "staying behind in the cytoplasm" is achieved by inhibitory proteins that bind to NF-kappaB and thus deactivate it. Among the stimuli that trigger the activation of NF-kappaB are UV rays, growth factors, cytokines (e.g. tumour necrosis factor-α and IL-1beta), bacterial and viral antigens (e.g. lipopolysaccharides, double-stranded RNA). Such stimulation causes a change in the activity of cellular signaling pathways, which are often mediated by phosphorylation. Among the signalling pathways important for NF-kappaB, the MAP kinase signalling pathway is also important. The activated and released NF-kappaB can now migrate into the nucleus, bind to DNA and stimulate the transcription of effector genes. NF-kappaB plays a major role in the development of sunburn after UV exposure.
Note(s)This section has been translated automatically.
Another example of genes regulated by NF-kappaB is the cyclooxygenase 2 gene (see cyclooxygenases below). It is likely that cyclooxygenase 2 is increasingly transcribed by NF-kappaB.