TAZ: a novel transcriptional co-activator regulated by interactions with 14-3-3 and PDZ domain proteins.
The highly conserved and ubiquitously expressed 14-3-3 proteins regulate differentiation, cell cycle progression and apoptosis by binding intracellular phosphoproteins involved in signal transduction. By screening in vitro translated cDNA pools for the ability to bind 14-3-3, we identified a novel transcriptional co-activator, TAZ (transcriptional co-activator with PDZ-binding motif) as a 14-3-3-binding molecule. TAZ shares homology with Yes-associated protein (YAP), contains a WW domain and functions as a transcriptional co-activator by binding to the PPXY motif present on transcription factors. 14-3-3 binding requires TAZ phosphorylation on a single serine residue, resulting in the inhibition of TAZ transcriptional co-activation through 14-3-3-mediated nuclear export. The C-terminus of TAZ contains a highly conserved PDZ-binding motif that localizes TAZ into discrete nuclear foci and is essential for TAZ-stimulated gene transcription. TAZ uses this same motif to bind the PDZ domain-containing protein NHERF-2, a molecule that tethers plasma membrane ion channels and receptors to cytoskeletal actin. TAZ may link events at the plasma membrane and cytoskeleton to nuclear transcription in a manner that can be regulated by 14-3-3.
Pubmed ID: 11118213 RIS Download
14-3-3 Proteins | Amino Acid Sequence | Animals | Binding Sites | Carrier Proteins | Cell Line | Chickens | DNA-Binding Proteins | Gene Expression Regulation | HeLa Cells | Humans | Mice | Molecular Sequence Data | Phosphorylation | Proteins | Recombinant Proteins | Sequence Alignment | Sequence Homology, Amino Acid | Transcription Factors | Tyrosine 3-Monooxygenase