title: Opposite effects of PU.1 on mast cell stimulation.
abstract: An Ets-family transcription factor PU.1 is involved in the development and specific gene regulation of hematopoietic cells. PU.1 also determines the commitment between several lineages via its expression level. Although enforced expression of PU.1 in mast cells (MC) induced expression of monocyte-specific markers and morphological change from MC to monocytes, especially dendritic cells (DC), in the previous report, intracellular events caused by PU.1 are largely unknown. In the present study, effect of PU.1 on IgE- and LPS-mediated stimulation degrees was analyzed. The amounts of IL-6, IL-13, and TNF-alpha produced from LPS-stimulated MC were markedly increased by overexpression of PU.1. In contrast, IL-6 and IL-13 production levels in response to IgE were reduced by PU.1, whereas that of TNF-alpha was up-regulated. beta-Hexosaminidase release as a means of degranulation was decreased in PU.1 transfectants. When eicosanoid generation in response to IgE-stimulation was analyzed, overexpression of PU.1 reduced leukotriene C(4) (LTC(4)) release, but enhanced PGD(2) production. Microarray analysis suggested that expression of FcepsilonRI signal pathway related molecules were suppressed in PU.1 overexpressing MC as well as DC. These observations indicate that up-regulation of PU.1 suppresses expression of FcepsilonRI signal transduction-related intracellular molecules, but increases the potential of transcription activity of monocyte characters.
authors.affiliation: Atopy (Allergy) Research Center, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Niwa
authors.forename: Chiharu
authors.initials: C
authors.lastname: Nishiyama
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Nakano
authors.forename: Asuka
authors.initials: A
authors.lastname: Kamei
authors.forename: Hisanori
authors.initials: H
authors.lastname: Kato
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Kanada
authors.forename: Shigaku
authors.initials: S
authors.lastname: Ikeda
authors.forename: Hideoki
authors.initials: H
authors.lastname: Ogawa
authors.forename: Ko
authors.initials: K
authors.lastname: Okumura
mesh_terms: D000818:Animals; D015550:Cell Degranulation / Q000235:genetics; D015777:Eicosanoids / Q000096:biosynthesis; D005786:Gene Expression Regulation; D007073:Immunoglobulin E / Q000276:immunology; D018793:Interleukin-13 / Q000096:biosynthesis; D015850:Interleukin-6 / Q000096:biosynthesis; D017997:Leukotriene C4 / Q000096:biosynthesis; D008070:Lipopolysaccharides / Q000276:immunology / Q000494:pharmacology; D008407:Mast Cells / Q000187:drug effects / Q000276:immunology*; D051379:Mice; D015230:Prostaglandin D2 / Q000096:biosynthesis; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000502:physiology*; D017455:Receptors, IgE / Q000378:metabolism*; D012190:Retroviridae; D015398:Signal Transduction; D015534:Trans-Activators / Q000235:genetics / Q000502:physiology*; D014162:Transfection; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D000099232:Proto-Oncogene Protein Spi-1
chemical_list: D015777:Eicosanoids; D007073:Immunoglobulin E; D018793:Interleukin-13; D015850:Interleukin-6; D017997:Leukotriene C4; D008070:Lipopolysaccharides; D015230:Prostaglandin D2; D011518:Proto-Oncogene Proteins; D017455:Receptors, IgE; D015534:Trans-Activators; D014409:Tumor Necrosis Factor-alpha; D000099232:Proto-Oncogene Protein Spi-1