Antiapoptotic role of the p38 mitogen-activated protein kinase-myocyte enhancer factor 2 transcription factor pathway during neuronal differentiation.
Myocyte enhancer factor 2 (MEF2) is in the MADS (MCM1agamous-deficiens-serum response factor) family of transcription factors. Although MEF2 is known as a myogenic factor, the expression pattern of the MEF2 family of genes (MEF2A-D) in developing brain also suggests a role in neurogenesis. Here we show that transfection with MEF2C, the predominant form in mammalian cerebral cortex, induces a mixed neuronal/myogenic phenotype in undifferentiated P19 precursor cells. During retinoic acid-induced neurogenesis of these cells, a dominant negative form of MEF2 enhances apoptosis but does not affect cell division. The mitogen-activated protein kinase p38alpha activates MEF2C. Dominant negative p38alpha also enhances apoptotic death of differentiating neurons, but these cells can be rescued from apoptosis by coexpression of constitutively active MEF2C. These findings suggest that the p38alpha/MEF2 pathway prevents cell death during neuronal differentiation.
Okamoto
S
S
Center for Neuroscience and Aging, The Burnham Institute, La Jolla, CA 92037, USA.
Krainc
D
D
Sherman
K
K
Lipton
S A
SA
D017209:Apoptosis / Q000502:physiology*; D002454:Cell Differentiation / Q000502:physiology; D004268:DNA-Binding Proteins / Q000502:physiology*; D006801:Humans; D026161:MADS Domain Proteins; D064326:MEF2 Transcription Factors; D020928:Mitogen-Activated Protein Kinases / Q000502:physiology*; D018006:Myogenic Regulatory Factors; D009474:Neurons / Q000166:cytology* / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D014157:Transcription Factors / Q000502:physiology*; D014162:Transfection; D014407:Tumor Cells, Cultured; D048051:p38 Mitogen-Activated Protein Kinases
D004268:DNA-Binding Proteins; D026161:MADS Domain Proteins; D064326:MEF2 Transcription Factors; C578035:MEF2A protein, human; C578040:MEF2C protein, human; D018006:Myogenic Regulatory Factors; D014157:Transcription Factors; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases