title: PU.1/Spi-B regulation of c-rel is essential for mature B cell survival.
abstract: PU.1(+/-)Spi-B(-/-) mice exhibit reduced numbers of immature and mature B lymphocytes, which exhibit severe defects in response to BCR-mediated stimulation and poor survival. We found that expression of c-rel, a member of the Rel/NF-kappa B family, is dramatically reduced in PU.1(+/-)Spi-B(-/-) splenic B cells. Analysis of the murine c-rel promoter identified three PU.1/Spi-B binding sites critical for c-rel promoter activity. Furthermore, reintroduction of Rel protein restored wild-type B cell numbers to mice reconstituted with PU.1(+/-)Spi-B(-/-) bone marrow. These findings are the first to demonstrate that a member of the Rel/NF-kappa B family is directly regulated by Ets proteins and dissect the molecular basis for the function of two Ets factors, PU.1 and Spi-B, in promoting B lymphocyte survival.
authors.affiliation: Abramson Family Cancer Research Institute, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
authors.forename: C J
authors.initials: CJ
authors.lastname: Hu
authors.forename: S
authors.initials: S
authors.lastname: Rao
authors.forename: D L
authors.initials: DL
authors.lastname: Ramirez-Bergeron
authors.forename: L A
authors.initials: LA
authors.lastname: Garrett-Sinha
authors.forename: S
authors.initials: S
authors.lastname: Gerondakis
authors.forename: M R
authors.initials: MR
authors.lastname: Clark
authors.forename: M C
authors.initials: MC
authors.lastname: Simon
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D001665:Binding Sites; D001854:Bone Marrow Cells / Q000276:immunology; D016026:Bone Marrow Transplantation; D002460:Cell Line; D002470:Cell Survival; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D015536:Down-Regulation; D005786:Gene Expression Regulation; D051379:Mice; D018345:Mice, Knockout; D011401:Promoter Regions, Genetic; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000502:physiology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics; D020569:Proto-Oncogene Proteins c-rel / Q000096:biosynthesis / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis; D013154:Spleen / Q000276:immunology; D015534:Trans-Activators / Q000235:genetics / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D014162:Transfection; D000099232:Proto-Oncogene Protein Spi-1
chemical_list: D004268:DNA-Binding Proteins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D020569:Proto-Oncogene Proteins c-rel; D012333:RNA, Messenger; D015534:Trans-Activators; D014157:Transcription Factors; D000099232:Proto-Oncogene Protein Spi-1; C076877:SPIB protein, human