The DREAM-DRE interaction: key nucleotides and dominant negative mutants

Transcriptional repressor DREAM, an EF-hand containing calcium-binding prot ein, blocks basal expression of target genes through specific interaction w ith DRE sites in the DNA. The sequence GTCA forms the central core of the D RE site, whereas flanking nucleotides contribute notably to the affinity fo r DREAM. Release of binding of DREAM from the DRE results in derepression, a process that is regulated by Ca2+. Change of two amino acids within an EF -hand in DREAM blocks Ca2+-induced derepression and results in potent domin ant negative mutants of endogenous DREAM. (C) 2000 Elsevier Science B.V. Al l rights reserved.