Highly conserved and ubiquitously expressed 14-3-3 proteins regulate differentiation, cell cycle progression and apoptosis by binding intracellular phosphoproteins involved in signal transduction. A novel transcriptional co-activator, TAZ (transcriptional co-activator with PDZ-binding motif) functions as a 14-3-3-binding molecule. TAZ may link events at the plasma membrane and cytoskeleton to nuclear transcription in a manner that can be regulated by 14-3-3.