NF-KAPPA-B AND REL PROTEINS - EVOLUTIONARILY CONSERVED MEDIATORS OF IMMUNE-RESPONSES

The transcription factor NF-KB, more than a decade after its discovery , remains an exciting and active area of study. The involvement of NF- kappa B in the expression of numerous cytokines and adhesion molecules has supported its role as an evolutionarily conserved coordinating el ement in the organism's response to situations of infection, stress, a nd injury. Recently, significant advances have been made in elucidatin g the details of the pathways through which signals are transmitted to the NF-kappa B:I kappa B complex in the cytosol. The field now awaits the discovery and characterization of the kinase responsible for the inducible phosphorylation of I kappa B proteins. Another exciting deve lopment has been the demonstration that in certain situations NF-kappa B acts as an anti-apoptotic protein; therefore, elucidation of the me chanism by which NF-kappa B protects against cell death is an importan t goal. Finally, the generation of knockouts of members of the NF-kapp a B/I kappa B family has allowed the study of the roles of these prote ins in normal development and physiology. In this review, we discuss s ome of these recent findings and their implications for the study of N F-kappa B.