title: Activation of the myocyte enhancer factor-2 transcription factor by calcium/calmodulin-dependent protein kinase-stimulated binding of 14-3-3 to histone deacetylase 5.
abstract: Skeletal muscle differentiation is controlled by interactions between myocyte enhancer factor-2 (MEF2) and myogenic basic helix-loop-helix transcription factors. Association of MEF2 with histone deacetylases (HDAC) -4 and -5 results in repression of MEF2 target genes and inhibition of myogenesis. Calcium/calmodulin-dependent protein kinase (CaMK) signaling promotes myogenesis by disrupting MEF2-HDAC complexes and stimulating HDAC nuclear export. To further define the mechanisms that confer CaMK responsiveness to HDAC4 and -5, we performed yeast two-hybrid screens to identify HDAC-interacting factors. These screens revealed interactions between HDAC4 and members of the 14-3-3 family of proteins, which function as signal-dependent intracellular chaperones. HDAC4 binds constitutively to 14-3-3 in yeast and mammalian cells, whereas HDAC5 binding to 14-3-3 is largely dependent on CaMK signaling. CaMK phosphorylates serines -259 and -498 in HDAC5, which subsequently serve as docking sites for 14-3-3. Our studies suggest that 14-3-3 binding to HDAC5 is required for CaMK-dependent disruption of MEF2-HDAC complexes and nuclear export of HDAC5, and implicate 14-3-3 as a signal-dependent regulator of muscle cell differentiation.
authors: Department of Molecular Biology, The University of Texas Southwestern Medical Center at Dallas, 6000 Harry Hines Boulevard, Dallas, TX 75390, USA.
authors: T A
authors: TA
authors: McKinsey
authors: C L
authors: CL
authors: Zhang
authors: E N
authors: EN
authors: Olson
mesh_terms: D048948:14-3-3 Proteins; D000818:Animals; D001665:Binding Sites; D001692:Biological Transport; D019556:COS Cells; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism; D002522:Chlorocebus aethiops; D004268:DNA-Binding Proteins / Q000378:metabolism*; D006655:Histone Deacetylases / Q000235:genetics / Q000378:metabolism*; D064326:MEF2 Transcription Factors; D051379:Mice; D018006:Myogenic Regulatory Factors; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae; D012694:Serine / Q000378:metabolism; D015398:Signal Transduction; D014157:Transcription Factors / Q000378:metabolism*; D014446:Tyrosine 3-Monooxygenase / Q000235:genetics / Q000378:metabolism*
chemical_list: D048948:14-3-3 Proteins; D004268:DNA-Binding Proteins; D064326:MEF2 Transcription Factors; D018006:Myogenic Regulatory Factors; D012097:Repressor Proteins; D014157:Transcription Factors; D012694:Serine; D014446:Tyrosine 3-Monooxygenase; D017871:Calcium-Calmodulin-Dependent Protein Kinases; C400300:HDAC4 protein, human; C498618:Hdac5 protein, mouse; D006655:Histone Deacetylases