The rel family of proteins.

The rel family of proteins can be defined as a group of proteins that share sequence homology over a 300 amino acid region termed the rel domain. The rel family comprises important regulatory proteins from a wide variety of species and includes the Drosophila morphogen dorsal, the mammalian transcription factor NF-kappa B, the avian oncogene v-rel, and the cellular proto-oncogene c-rel. Over the last two years it has become apparent that these proteins function as DNA-binding transcription factors, and that their activity is regulated at the level of subcellular localization.