NF-kappa B (nuclear factor kappa B) is a protein complex that plays a crucial role in regulating the transcription of genes involved in immune response, inflammation, cell proliferation, and cell survival. It acts as a transcription factor that can activate the expression of various genes involved in these processes.
NF-kappa B is typically present in an inactive state in the cytoplasm as a heterodimer composed of two subunits, p50 and p65. In this state, it is bound to its inhibitor protein, I kappa B. Upon activation by various stimuli such as cytokines, viral or bacterial infection, or stress signals, I kappa B is phosphorylated and degraded, allowing NF-kappa B to translocate into the nucleus.
In the nucleus, the activated NF-kappa B complex binds to specific DNA sequences called kappa B sites, which are present in the promoter regions of target genes. This binding leads to the recruitment of co-activators and RNA polymerase, resulting in the transcription of genes involved in immune and inflammatory responses. These genes encode proteins such as cytokines, chemokines, cell adhesion molecules, and enzymes that contribute to the initiation and progression of various diseases.
The activation of NF-kappa B is tightly regulated, as its dysregulation can result in chronic inflammation, autoimmune disorders, and cancer. Therefore, it serves as a critical target for therapeutic interventions aimed at modulating immune and inflammatory responses.
