The nuclear factor kappa B (NFB)/Rel signal transduction pathway is conserved from simple multicellular eukaryotes, such as sponges and insects, to humans and controls a variety of processes involved primarily in immunity and development. The NFB family of transcription factors includes several structurally related proteins that form dimers, which regulate the expression of numerous genes by binding to specific deoxyribonucleic acid (DNA) sites near these genes. In mammals, the NFB pathway is important in the control of innate and adaptive immunity, immune cell development, cell proliferation and cell survival. In insects, the NFB pathway controls the establishment of dorsalventral polarity in the early embryo and an antimicrobial response. Activation of NFB transcription factors occurs via a series of biochemical steps and involves translocation of NFB from the cytoplasm to the nucleus where it can activate gene expression. Misregulation of the NFB pathway is also implicated in several human disease states, including many types of cancer and inflammatory diseases.
Key concepts:
- NFB and Rel proteins are part of a family of transcription factors whose activity is controlled primarily by subcellular localization.
- Many extracellular signals can activate a multicomponent signal transduction pathway that leads to nuclear localization of NFB/Rel proteins where they control the transcription of many important effector genes.
- NFB/Rel transcription factors control a number of evolutionarily conserved developmental and immune processes.
- In Drosophila, NFB/Rel signalling controls the immune response of flies to fungal and bacterial infections.
- In vertebrates, NFB/Rel signalling controls the innate immune response, cell survival and the development of several specific cell types, such as liver cells, immune cells and skin cells.
- Misregulation of NFB/Rel activity occurs in a number of human diseases, including several chronic inflammatory diseases and cancers.
Keywords: NF-kappaB; Rel; Dorsal; transcription factor; immune response






