title: Histone 3 lysine 9 (H3K9) methyltransferase recruitment to the interleukin-2 (IL-2) promoter is a mechanism of suppression of IL-2 transcription by the transforming growth factor-β-Smad pathway.
abstract: Suppression of IL-2 βproduction from T cells is an important process for the immune regulation by TGF-β. However, the mechanism by which this suppression occurs remains to be established. Here, we demonstrate that Smad2 and Smad3, two major TGF-β-downstream transcription factors, are redundantly essential for TGF-β-mediated suppression of IL-2 production in CD4(+) T cells using Smad2- and Smad3-deficient T cells. Both Smad2 and Smad3 were recruited into the proximal region of the IL-2 promoter in response to TGF-β. We then investigated the histone methylation status of the IL-2 promoter. Although both histone H3 lysine 9 (H3K9) and H3K27 trimethylation have been implicated in gene silencing, only H3K9 trimethylation was increased in the proximal region of the IL-2 promoter in a Smad2/3-dependent manner, whereas H3K27 trimethylation was not. The H3K9 methyltransferases Setdb1 and Suv39h1 bound to Smad3 and suppressed IL-2 promoter activity in collaboration with Smad3. Overexpression of Suv39h1 in 68-41 T cells strongly inhibited IL-2 production in response to T cell receptor stimulation irrespective of the presence or absence of TGF-β, whereas Setdb1 overexpression only slightly suppressed IL-2 production. Silencing of Suv39h1 by shRNA reverted the suppressive effect of TGF-β on IL-2 production. Furthermore, TGF-β induced Suv39h1 recruitment to the proximal region of the IL-2 promoter in wild type primary T cells; however, this was not observed in Smad2(-/-)Smad3(+/-) T cells. Thus, we propose that Smads recruit H3K9 methyltransferases Suv39h1 to the IL-2 promoter, thereby inducing suppressive histone methylation and inhibiting T cell receptor-mediated IL-2 transcription.
authors.affiliation: Department of Microbiology and Immunology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan and Japan Science and Technology Agency, CREST, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Wakabayashi
authors.affiliation: Department of Microbiology and Immunology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan and Japan Science and Technology Agency, CREST, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Taiga
authors.initials: T
authors.lastname: Tamiya
authors.affiliation: Department of Microbiology and Immunology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan and Japan Science and Technology Agency, CREST, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Takada
authors.affiliation: Department of Microbiology and Immunology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan and Japan Science and Technology Agency, CREST, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Fukaya
authors.affiliation: Department of Microbiology and Immunology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan and Japan Science and Technology Agency, CREST, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Sugiyama
authors.affiliation: Department of Microbiology and Immunology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan and Japan Science and Technology Agency, CREST, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Naoko
authors.initials: N
authors.lastname: Inoue
authors.affiliation: Department of Microbiology and Immunology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan and Japan Science and Technology Agency, CREST, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Kimura
authors.affiliation: Department of Microbiology and Immunology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan and Japan Science and Technology Agency, CREST, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Rimpei
authors.initials: R
authors.lastname: Morita
authors.affiliation: Department of Microbiology and Immunology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan and Japan Science and Technology Agency, CREST, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Ikko
authors.initials: I
authors.lastname: Kashiwagi
authors.affiliation: Department of Microbiology and Immunology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan and Japan Science and Technology Agency, CREST, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Tomohito
authors.initials: T
authors.lastname: Takimoto
authors.affiliation: Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Nomura
authors.affiliation: Department of Microbiology and Immunology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan and Japan Science and Technology Agency, CREST, Chiyoda-ku, Tokyo 102-0075, Japan. Electronic address: yoshimura@a6.keio.jp.
authors.forename: Akihiko
authors.initials: A
authors.lastname: Yoshimura
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism*; D002478:Cells, Cultured; D020868:Gene Silencing; D000076983:Histone Methyltransferases; D011495:Histone-Lysine N-Methyltransferase / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D006657:Histones / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D007376:Interleukin-2 / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology; D008745:Methylation; D008780:Methyltransferases / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D011401:Promoter Regions, Genetic / Q000502:physiology*; D012097:Repressor Proteins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D051899:Smad2 Protein / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D051900:Smad3 Protein / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D014158:Transcription, Genetic / Q000502:physiology*; D016212:Transforming Growth Factor beta / Q000235:genetics / Q000276:immunology / Q000378:metabolism*
chemical_list: D006657:Histones; D007376:Interleukin-2; D012097:Repressor Proteins; D051899:Smad2 Protein; C497783:Smad2 protein, mouse; D051900:Smad3 Protein; C497791:Smad3 protein, mouse; D016212:Transforming Growth Factor beta; C498700:Suv39h1 protein, mouse; D000076983:Histone Methyltransferases; D008780:Methyltransferases; D011495:Histone-Lysine N-Methyltransferase