Reciprocal regulation of adipogenesis by Myc and C/EBP alpha.
3T3-L1 adipoblasts that express large amounts of c-Myc cannot terminally differentiate, raising the possibility that Myc inhibits the expression of genes that promote adipogenesis. The CCAAT/enhancer binding protein (C/EBP alpha) is induced during 3T3-L1 adipogenesis when cells commit to the differentiation pathway. Transfection of 3T3-L1 adipoblasts with the gene that encodes C/EBP alpha caused overt expression of the adipocyte morphology. Expression of Myc prohibited the normal induction of C/EBP alpha and prevented adipogenesis. Enforced expression of C/EBP alpha overcame the Myc-induced block to differentiation. These results provide a molecular basis for the regulation of adipogenesis and implicate Myc and C/EBP alpha as pivotal controlling elements.
Freytag
S O
SO
Molecular Biology Research Program, Henry Ford Hospital, Detroit, MI 48202.
Geddes
T J
TJ
D000273:Adipose Tissue / Q000166:cytology* / Q000378:metabolism; D000818:Animals; D001483:Base Sequence; D022762:CCAAT-Enhancer-Binding Proteins; D002454:Cell Differentiation; D002455:Cell Division; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D005786:Gene Expression Regulation; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics / Q000502:physiology*; D010957:Plasmids; D016133:Polymerase Chain Reaction; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D014162:Transfection
D022762:CCAAT-Enhancer-Binding Proteins; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D016271:Proto-Oncogene Proteins c-myc; D012333:RNA, Messenger