title: Cutting edge: IL-4 production by mast cells does not require c-maf.
abstract: The c-maf transcription factor is selectively expressed in IL-4-producing Th2 cells. It has been implicated in IL-4 gene transcription based on its ability to directly activate the IL-4 gene in nonexpressing B cells and to promote IL-4-induced Th2 differentiation. However, it has not been definitively shown that IL-4 production by other cells is dependent on the presence of c-maf. Here, we show that IL-4-producing mast cells do not express the c-maf factor. Furthermore, mutation of a defined c-maf binding site within the proximal IL-4 promoter, which profoundly affects transcription in T cells, has no effect on expression of a reporter gene driven by the IL-4 promoter in mast cells. These results demonstrate that c-maf and its target binding site are not required for IL-4 production in all cell types and delineate additional cis- and trans-acting elements that contribute to the cell-type specific transcriptional regulation of IL-4.
authors.affiliation: Emory University School of Medicine, Department of Experimental Pathology, Graduate Program in Immunology, Atlanta, GA 30322, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Sherman
authors.forename: T Y
authors.initials: TY
authors.lastname: Nachman
authors.forename: M A
authors.initials: MA
authors.lastname: Brown
mesh_terms: D000818:Animals; D002460:Cell Line; D002461:Cell Line, Transformed; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D006801:Humans; D015847:Interleukin-4 / Q000096:biosynthesis* / Q000235:genetics; D019169:Jurkat Cells; D008407:Mast Cells / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D011401:Promoter Regions, Genetic / Q000276:immunology; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D051257:Proto-Oncogene Proteins c-maf; D012333:RNA, Messenger / Q000096:biosynthesis; D020218:Response Elements / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; C495607:MAF protein, human; C495608:Maf protein, mouse; D011518:Proto-Oncogene Proteins; D051257:Proto-Oncogene Proteins c-maf; D012333:RNA, Messenger; D015847:Interleukin-4