title: MED26 regulates the transcription of snRNA genes through the recruitment of little elongation complex.
abstract: Regulation of transcription elongation by RNA polymerase II (Pol II) is a key regulatory step in gene transcription. Recently, the little elongation complex (LEC)-which contains the transcription elongation factor ELL/EAF-was found to be required for the transcription of Pol II-dependent small nuclear RNA (snRNA) genes. Here we show that the human Mediator subunit MED26 plays a role in the recruitment of LEC to a subset of snRNA genes through direct interaction of EAF and the N-terminal domain (NTD) of MED26. Loss of MED26 in cells decreases the occupancy of LEC at a subset of snRNA genes and results in a reduction in their transcription. Our results suggest that the MED26-NTD functions as a molecular switch in the exchange of TBP-associated factor 7 (TAF7) for LEC to facilitate the transition from initiation to elongation during transcription of a subset of snRNA genes.
authors.affiliation: Department of Biochemistry, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan.
authors.forename: Hidehisa
authors.initials: H
authors.lastname: Takahashi
authors.affiliation: Creative Research Institution, Hokkaido University, Kita 21, Nishi 10, Kita-ku, Sapporo, Hokkaido 060-8638, Japan.
authors.forename: Ichigaku
authors.initials: I
authors.lastname: Takigawa
authors.affiliation: Department of Biochemistry, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Watanabe
authors.affiliation: Department of Biochemistry, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan.
authors.forename: Delnur
authors.initials: D
authors.lastname: Anwar
authors.affiliation: Department of Biochemistry, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan.
authors.forename: Mio
authors.initials: M
authors.lastname: Shibata
authors.affiliation: Stowers Institute for Medical Research, 1000 E, 50th Street, Kansas City, Missouri 64110, USA.
authors.forename: Chieri
authors.initials: C
authors.lastname: Tomomori-Sato
authors.affiliation: Stowers Institute for Medical Research, 1000 E, 50th Street, Kansas City, Missouri 64110, USA.
authors.forename: Shigeo
authors.initials: S
authors.lastname: Sato
authors.affiliation: Stowers Institute for Medical Research, 1000 E, 50th Street, Kansas City, Missouri 64110, USA.
authors.forename: Amol
authors.initials: A
authors.lastname: Ranjan
authors.affiliation: Stowers Institute for Medical Research, 1000 E, 50th Street, Kansas City, Missouri 64110, USA.
authors.forename: Chris W
authors.initials: CW
authors.lastname: Seidel
authors.affiliation: Department of Biochemistry, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan.
authors.forename: Tadasuke
authors.initials: T
authors.lastname: Tsukiyama
authors.affiliation: Department of Biochemistry, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Mizushima
authors.affiliation: Department of Advanced Medical Initiatives, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Masayasu
authors.initials: M
authors.lastname: Hayashi
authors.affiliation: Department of Advanced Medical Initiatives, Kyushu University Graduate School of Medical Sciences, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Ohkawa
authors.affiliation: 1] Stowers Institute for Medical Research, 1000 E, 50th Street, Kansas City, Missouri 64110, USA [2] Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City KS 66160, USA.
authors.forename: Joan W
authors.initials: JW
authors.lastname: Conaway
authors.affiliation: 1] Stowers Institute for Medical Research, 1000 E, 50th Street, Kansas City, Missouri 64110, USA [2] Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City KS 66160, USA.
authors.forename: Ronald C
authors.initials: RC
authors.lastname: Conaway
authors.affiliation: Department of Biochemistry, Hokkaido University Graduate School of Medicine, Kita 15, Nishi 7, Kita-ku, Sapporo, Hokkaido 060-8638, Japan.
authors.forename: Shigetsugu
authors.initials: S
authors.lastname: Hatakeyama
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D004257:DNA Polymerase II / Q000378:metabolism; D005347:Fibroblasts / Q000378:metabolism; D057809:HEK293 Cells; D006367:HeLa Cells; D006801:Humans; D056892:Mediator Complex / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D010441:Peptide Chain Elongation, Translational; D017354:Point Mutation; D011485:Protein Binding; D012342:RNA, Small Nuclear / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D061987:Sf9 Cells; D035381:TATA-Binding Protein Associated Factors / Q000378:metabolism; D035362:Transcription Factor TFIID / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: C431383:EAF1 protein, human; C492155:MED26 protein, human; D056892:Mediator Complex; D012342:RNA, Small Nuclear; D011994:Recombinant Proteins; C091537:TAF7 protein, human; D035381:TATA-Binding Protein Associated Factors; D035362:Transcription Factor TFIID; D014157:Transcription Factors; D004257:DNA Polymerase II