NF-kappaB

Nuclear factor kappa-light-chain-enhancer of activated B cells
Identifiers
Symbol	NF-κB

Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) is a protein complex that plays a key role in regulating the immune system response to infection. NF-κB is involved in cellular responses to stimuli such as stress, cytokines, free radicals, ultraviolet irradiation, and bacterial or viral antigens. It is found in almost all animal cell types and is involved in cellular responses to stimuli. NF-κB plays a key role in regulating the immune response to infection. Consisting of various proteins, it acts as a transcription factor regulating the expression of genes related to cell survival, cytokine production, and other critical functions of the immune system.

Structure and Function

NF-κB is a protein complex that is composed of several subunits. The most common form of NF-κB is a heterodimer consisting of p50 and p65 subunits. These proteins are held in the cytoplasm in an inactive state by the inhibitor IκB. Upon activation, IκB is degraded, allowing NF-κB to enter the nucleus and activate genes involved in inflammation, immune response, cell adhesion, differentiation, proliferation, and survival.

Activation

NF-κB can be activated by a variety of signals, including those from Toll-like receptors (TLRs), T cell receptors (TCRs), and B cell receptors (BCRs), which recognize components of pathogens or damaged cells. This activation involves the phosphorylation and subsequent degradation of IκB by the IκB kinase complex (IKK). Once free of IκB, NF-κB moves to the nucleus and binds to specific sequences in DNA, called response elements, to regulate gene transcription.

Role in Disease

Dysregulation of NF-κB has been linked to cancer, inflammatory and autoimmune diseases, septic shock, viral infection, and improper immune development. Its role in promoting inflammation makes it a potential therapeutic target for anti-inflammatory drugs.

Research and Therapeutic Approaches

Research into NF-κB has led to the development of drugs aimed at inhibiting its activation. These include inhibitors of IKK and proteasome inhibitors, which prevent the degradation of IκB, thus keeping NF-κB inactive.

See Also

• Cytokine
• Immune system
• Transcription factor