title: The evolutionally-conserved function of group B1 Sox family members confers the unique role of Sox2 in mouse ES cells.
abstract: In mouse ES cells, the function of Sox2 is essential for the maintenance of pluripotency. Since the Sox-family of transcription factors are well conserved in the animal kingdom, addressing the evolutionary origin of Sox2 function in pluripotent stem cells is intriguing from the perspective of understanding the origin of pluripotency.
  
  
  
  Here we approach this question using a functional complementation assay in inducible Sox2-null ES cells. Assaying mouse Sox proteins from different Groups, we found that only Group B1 and Group G proteins were able to support pluripotency. Interestingly, invertebrate homologs of mammalian Group B1 Sox proteins were able to replace the pluripotency-associated function of mouse Sox2. Moreover, the mouse ES cells rescued by the Drosophila SoxNeuro protein are able to contribute to chimeric embryos.
  
  
  
  These data indicate that the function of mouse Sox2 supporting pluripotency is based on an evolutionally conserved activity of the Group B1 Sox family. Since pluripotent stem cell population in developmental process could be regarded as the evolutional novelty in vertebrates, it could be regarded as a co-optional use of their evolutionally conserved function.
authors: Laboratory for Pluripotent Stem Cell Studies, RIKEN Center for Developmental Biology (CDB), 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, 650-0047, Japan. niwa@kumamoto-u.ac.jp.|Department of Pluripotent Stem Cell Biology, Institute of Molecular Embryology and Genetics, Kumamoto University, 2-2-1 Honjo, Chuo-ku, Kumamoto, 860-0811, Japan. niwa@kumamoto-u.ac.jp.
authors: Hitoshi
authors: 0000-0002-5280-8031
authors: H
authors: Niwa
authors: Department of Germline Development, Institute of Molecular Embryology and Genetics, Kumamoto University, 2-2-1 Honjo, Chuo-ku, Kumamoto, 860-0811, Japan.
authors: Akira
authors: A
authors: Nakamura
authors: Noto Marine Laboratory, Institute of Nature and Environmental Technology, Kanazawa University, Ogi 34-11, Noto-cho, Hohsu, Ishikawa, 927-0553, Japan.
authors: Makoto
authors: M
authors: Urata
authors: Sugashima Marine Biological Laboratory, Graduate School of Science, Nagoya University, Sugashima-cho 429-63, Toba C, Mie, 517-0004, Japan.
authors: Maki
authors: M
authors: Shirae-Kurabayashi
authors: Phyloinformatics Unit, RIKEN Center for Life Science Technologies (CLST), 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, 650-0047, Japan.
authors: Shigehiro
authors: S
authors: Kuraku
authors: Department of Genetics, University of Cambridge, Downing Street, Cambridge, CB2 3EH, UK.
authors: Steven
authors: S
authors: Russell
authors: Laboratory for Pluripotent Stem Cell Studies, RIKEN Center for Developmental Biology (CDB), 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, 650-0047, Japan.|Present address: Department of Life Science, Medical Research Institute, Kanazawa Medical University, 1-1 Daigaku, Uchinada, kahoku, Ishikawa, 920-0293, Japan.
authors: Satoshi
authors: S
authors: Ohtsuka
mesh_terms: D000818:Animals; D004330:Drosophila; D029721:Drosophila Proteins / Q000235:genetics; D053595:Embryonic Stem Cells; D019143:Evolution, Molecular; D005260:Female; D051379:Mice; D008810:Mice, Inbred C57BL; D008813:Mice, Inbred ICR; D039904:Pluripotent Stem Cells; D055747:SOX Transcription Factors / Q000235:genetics; D055748:SOXB1 Transcription Factors / Q000235:genetics*
chemical_list: D029721:Drosophila Proteins; D055747:SOX Transcription Factors; D055748:SOXB1 Transcription Factors; C527783:Sox2 protein, mouse; C412366:SoxN protein, Drosophila
keywords: Co-option; Evolution; Pluripotent stem cells; Sox2