Nucleic Acids Research, 1988, Vol. 16, No. 24 11417-11430
© 1988
MOLECULAR BIOLOGY |
The regulation of SV40 early gene expression in embryonal carcinoma stem cells-faithful transcriptional regulation in vitro
Cancer Research Campaign, Eukaryotic Molecular Genetics Research Group, Department of Biochemistry, Imperial College of Science and Technology London, SW7 2AZ and Laboratory of Eukaryotic Molecular Genetics, National Institute for Medical Research The Ridgeway, Mill Hill, London, NW7 1AA, UK
*Present Address. Laboratory of Eukaryotic Molecular Genetics, National Institute for Medical Research, The Ridgeway, Mill Hill, London, NW7 1AA, UK
Received October 19, 1988. Accepted November 18, 1988.
We have derived from F9 murine embryonal carcinoma stem cells, and from differentiated derivatives induced with retinoic acid and cAMP, whole cell extracts which efficiently and accurately transcribe a variety of supercoiled DNA templates in vitro. These extracts and control elements from viral genomes have been used to study changes in transcriptional activity which accompany differentiation. The SV40 enhancer is inefficiently utilized in stem cells but is activated upon differentiation to parietal endoderm and the in vitro systems mimick this regulation. Mixing experiments demonstrate that the differentiated cell phenotype is dominant, suggesting that stem cells contain limiting amounts of factors required for enhancer activity. Our results may explain the developmental regulation of cellular genes with enhancer motifs in their control sequences.