title: Critical role for the Oct-2/OCA-B partnership in Ig-secreting cells.
abstract: B and T lymphocytes arise from a common precursor in the bone marrow, but ultimately acquire very different functions. The difference in function is largely attributable to the expression of tissue-specific transcription factors that activate discrete sets of genes. In previous studies we and others have shown that the specialized genes expressed by Ig-secreting cells cease transcription when these cells are fused to a T lymphoma. The extinguished genes include those encoding Ig, J chain, and the transcription factors Oct-2, PU.1, and the coactivator OCA-B. Remarkably, if we sustain Oct-2 expression during cell fusion, all the other tissue-specific genes of the Ig-secreting cell simultaneously escape silencing. This suggests that Oct-2 plays a central role in maintaining the gene expression program of these cells. In the present studies we have investigated the roles of the transcription factor PU.1 and the coactivator OCA-B within the hierarchy of regulatory factors that sustain Ig-secreting cell function. Our results show that OCA-B and Oct-2 are regulatory partners in this process and that PU.1 plays a subordinate role at this cell stage.
authors.affiliation: Department of Biological Sciences, Hunter College and Graduate Center of City University of New York, New York, NY 10021, USA.
authors.forename: Mabel
authors.initials: M
authors.lastname: Salas
authors.forename: Laurel A
authors.initials: LA
authors.lastname: Eckhardt
mesh_terms: D000818:Animals; D002459:Cell Fusion; D045744:Cell Line, Tumor; D002999:Clone Cells; D004268:DNA-Binding Proteins / Q000502:physiology*; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology; D006801:Humans; D006825:Hybridomas; D007136:Immunoglobulins / Q000096:biosynthesis*; D016399:Lymphoma, T-Cell / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008806:Mice, Inbred AKR; D008807:Mice, Inbred BALB C; D018345:Mice, Knockout; D018146:Muromegalovirus / Q000235:genetics; D050813:Octamer Transcription Factor-2; D010641:Phenotype; D010954:Plasmacytoma / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000172:deficiency / Q000235:genetics / Q000502:physiology; D015534:Trans-Activators / Q000096:biosynthesis / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D014157:Transcription Factors / Q000502:physiology*; D014162:Transfection; D019076:Transgenes; D000099232:Proto-Oncogene Protein Spi-1
chemical_list: D004268:DNA-Binding Proteins; D007136:Immunoglobulins; D050813:Octamer Transcription Factor-2; D011518:Proto-Oncogene Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D000099232:Proto-Oncogene Protein Spi-1; C091546:POU2AF1 protein, human; C058435:POU2F2 protein, human; C490424:Pou2af1 protein, mouse; C489206:Pou2f2 protein, mouse