title: The octamer motif present in the Rex-1 promoter binds Oct-1 and Oct-3 expressed by EC cells and ES cells.
abstract: Rex-1 is a zinc finger-containing gene that is expressed in embryonal carcinoma (EC) cells and embryonic stem (ES) cells. Upon differentiation with retinoic acid (RA), transcription of the Rex-1 gene decreases rapidly. Analysis of the 5'-flanking region of the Rex-1 gene identified a consensus motif for the octamer family of transcription factors that stimulates expression from the Rex-1 promoter. In this report, we utilized gel mobility shift analysis to examine the binding of transcription factors to the Rex-1 octamer motif. F9 EC cells, D3 ES cells, and human NT2/D1 EC cells each from at least two prominent DNA/protein complexes with the octamer motif. Supershift analysis identifies Oct-1 and Oct-3 in these complexes. When F9 EC cells are induced to differentiate by treatment with RA for 48 h, there is a complete loss of the DNA/protein complex containing Oct-3. In contrast, the other DNA/protein complexes, including the DNA/protein complex containing Oct-1, can still be detected. These results provide support for a role of Oct-3 in the transcription of the Rex-1 gene.
authors.affiliation: Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha 68198-6805.
authors.forename: E
authors.initials: E
authors.lastname: Rosfjord
authors.forename: A
authors.initials: A
authors.lastname: Rizzino
mesh_terms: D000818:Animals; D001483:Base Sequence; D018236:Carcinoma, Embryonal / Q000378:metabolism*; D002454:Cell Differentiation / Q000502:physiology; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000378:metabolism*; D004622:Embryo, Mammalian; D015870:Gene Expression; D016355:Genes, pX; D051863:Host Cell Factor C1; D051379:Mice; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000302:isolation & purification / Q000378:metabolism; D050811:Octamer Transcription Factor-1; D050814:Octamer Transcription Factor-3; D011401:Promoter Regions, Genetic; D013234:Stem Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D014157:Transcription Factors / Q000096:biosynthesis / Q000378:metabolism*; D014158:Transcription, Genetic; D014212:Tretinoin / Q000494:pharmacology; D014407:Tumor Cells, Cultured
chemical_list: D004268:DNA-Binding Proteins; C497693:Hcfc1 protein, mouse; D051863:Host Cell Factor C1; D009687:Nuclear Proteins; D050811:Octamer Transcription Factor-1; D050814:Octamer Transcription Factor-3; C494166:Pou2f1 protein, mouse; C494174:Pou5f1 protein, mouse; D014157:Transcription Factors; D014212:Tretinoin