Differential role of p300 and CBP acetyltransferase during myogenesis: p300 acts upstream of MyoD and Myf5.

Studies in tissue culture cells have implicated p300 and CBP acetyltransferases in myogenic regulatory factor (MRF) mediated transcription and terminal differentiation of skeletal muscle cells. However, in vivo data placing p300 and CBP on myogenic differentiation pathways are not yet available. In this report we provide genetic evidence that p300 but not CBP acetyltransferase (AT) activity is required for myogenesis in the mouse and in embryonic stem (ES) cells.

Essential function of p300 acetyltransferase activity in heart, lung and small intestine formation.

p300 and CBP are large nuclear acetyltransferases exhibiting a complex multi-domain structure. Mouse embryos nullizygous for either p300 or Cbp die at midgestation, while heterozygotes are viable but in part display defects in neurulation or bone morphogenesis. To directly examine the contribution of the acetyltransferase (AT) activity to mouse development, we have abrogated this function by a knock-in approach.