title: Etv1 and Ewsr1 cooperatively regulate limb mesenchymal Fgf10 expression in response to apical ectodermal ridge-derived fibroblast growth factor signal.
abstract: Fibroblast growth factors (FGFs) expressed in the apical ectodermal ridge (AER) and FGF10 expressed in the underlying mesoderm are essential for limb bud outgrowth. Their expression is maintained through a positive feedback loop. We identified the cis-regulatory element and trans-acting factors involved in the AER-FGF-dependent transactivation of Fgf10. Etv1 and Ewsr1 stimulated transcription from the Fgf10 promoter in the sub-AER mesenchyme of mouse and chick limb buds in a conserved AGAAAR cluster-dependent manner. We found that both Etv1 and Ewsr1 were necessary for Fgf10 expression and elongation of the limb bud. In addition, Etv1 and AER-FGF synergistically stimulated Fgf10 promoter activity in an Ewsr1-dependent manner. We also found that Etv1 and Ewsr1 bound to the segment of DNA containing the AGAAAR cluster in vivo and in vitro. Moreover, Etv1 directly bound to the AGAAAR sequence in vitro. Our results suggest that Etv1 and Ewsr1 transactivate Fgf10 directly and cooperatively in response to AER-FGFs.
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan.
authors.forename: Yo-Ichi
authors.initials: Y
authors.lastname: Yamamoto-Shiraishi
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Higuchi
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan.
authors.forename: Shigeki
authors.initials: S
authors.lastname: Yamamoto
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan.
authors.forename: Mie
authors.initials: M
authors.lastname: Hirano
authors.affiliation: Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602, Japan. Electronic address: akuro@nagoya-u.jp.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Kuroiwa
mesh_terms: D000818:Animals; D001665:Binding Sites / Q000235:genetics; D002478:Cells, Cultured; D002642:Chick Embryo; D004268:DNA-Binding Proteins / Q000378:metabolism*; D004475:Ectoderm / Q000378:metabolism; D051526:Fibroblast Growth Factor 10 / Q000096:biosynthesis* / Q000235:genetics; D005346:Fibroblast Growth Factors / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental; D018878:Limb Buds / Q000254:growth & development*; D008648:Mesoderm / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D011401:Promoter Regions, Genetic; D011494:Protein Kinases / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering; D034802:RNA-Binding Protein EWS / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*
chemical_list: D004268:DNA-Binding Proteins; C490641:Etv1 protein, mouse; C496464:Fgf10 protein, mouse; D051526:Fibroblast Growth Factor 10; D034741:RNA, Small Interfering; D034802:RNA-Binding Protein EWS; D014157:Transcription Factors; D005346:Fibroblast Growth Factors; D011494:Protein Kinases; C065999:Sp1 kinase
keywords: Ets family transcription factor; Ewsr1; FGF; Limb bud elongation; Mek; Tissue interaction