Ectopic expression of the CCAAT/enhancer-binding protein alpha promotes the adipogenic program in a variety of mouse fibroblastic cells.
The CCAAT/enhancer-binding protein alpha (C/EBP alpha) has been implicated in the regulation of adipoblast differentiation. In this study we investigate the potential of C/EBP alpha to promote the adipogenic program in a variety of fibroblastic cells. Transduction of the C/EBP alpha gene into eight mouse fibroblastic cell lines by retroviruses and DNA transfection generates adipocyte colonies at variable frequencies. The most dramatic results are obtained with NIH-3T3 cells, in which the percentage of G418-resistant colonies that exhibit the adipocyte morphology is reproducibly > 50% when the C/EBP alpha gene is transduced by retroviruses. The ability to promote the adipogenic program requires the potent transcriptional activation domain of C/EBP alpha and is not observed with C/EBP beta. Paradoxically, in spite of its antimitogenic effects, clonal cell lines that stably express high amounts of C/EBP alpha can readily be generated. Stable expression of C/EBP alpha in BALB/c-3T3 cells dramatically enhances their ability to terminally differentiate into adipocytes. The results demonstrate that C/EBP alpha can efficiently promote the adipogenic program in a variety of mouse fibroblastic cells, including those that have little or no spontaneous capacity to undergo adipogenesis.
Freytag
S O
SO
Molecular Biology Research Program, Case Western Reserve University, Henry Ford Health Sciences Center, Detroit, Michigan 48202.
Paielli
D L
DL
Gilbert
J D
JD
D016475:3T3 Cells; D017667:Adipocytes / Q000166:cytology*; D000818:Animals; D001483:Base Sequence; D022762:CCAAT-Enhancer-Binding Proteins; D002454:Cell Differentiation; D002460:Cell Line; D015500:Chloramphenicol O-Acetyltransferase / Q000096:biosynthesis; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000096:biosynthesis*; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism; D015870:Gene Expression; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000096:biosynthesis*; D016133:Polymerase Chain Reaction; D011347:Procollagen / Q000096:biosynthesis; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000378:metabolism; D014162:Transfection
D022762:CCAAT-Enhancer-Binding Proteins; D017931:DNA Primers; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; D011347:Procollagen; D012333:RNA, Messenger; D015500:Chloramphenicol O-Acetyltransferase