title: Quadruple zebrafish mutant reveals different roles of Mesp genes in somite segmentation between mouse and zebrafish.
abstract: The segmental pattern of somites is generated by sequential conversion of the temporal periodicity provided by the molecular clock. Whereas the basic structure of this clock is conserved among different species, diversity also exists, especially in terms of the molecular network. The temporal periodicity is subsequently converted into the spatial pattern of somites, and Mesp2 plays crucial roles in this conversion in the mouse. However, it remains unclear whether Mesp genes play similar roles in other vertebrates. In this study, we generated zebrafish mutants lacking all four zebrafish Mesp genes by using TALEN-mediated genome editing. Contrary to the situation in the mouse Mesp2 mutant, in the zebrafish Mesp quadruple mutant embryos the positions of somite boundaries were clearly determined and morphological boundaries were formed, although their formation was not completely normal. However, each somite was caudalized in a similar manner to the mouse Mesp2 mutant, and the superficial horizontal myoseptum and lateral line primordia were not properly formed in the quadruple mutants. These results clarify the conserved and species-specific roles of Mesp in the link between the molecular clock and somite morphogenesis.
authors.affiliation: Division of Molecular and Developmental Biology, Okazaki Institute for Integrative Bioscience and National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan Department for Basic Biology, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan.
authors.forename: Taijiro
authors.initials: T
authors.lastname: Yabe
authors.affiliation: Department of Human Genetics, University of Utah, Salt Lake City, UT 84112, USA.
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Hoshijima
authors.affiliation: Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Hiroshima 739-8526, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamamoto
authors.affiliation: Division of Molecular and Developmental Biology, Okazaki Institute for Integrative Bioscience and National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Aichi 444-8787, Japan Department for Basic Biology, SOKENDAI (The Graduate University for Advanced Studies), Okazaki, Aichi 444-8787, Japan stakada@nibb.ac.jp.
authors.forename: Shinji
authors.identifier: 0000-0003-4125-6056
authors.initials: S
authors.lastname: Takada
mesh_terms: D000818:Animals; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism; D019521:Body Patterning / Q000235:genetics / Q000502:physiology; D018507:Gene Expression Regulation, Developmental / Q000235:genetics / Q000502:physiology; D051379:Mice; D009024:Morphogenesis / Q000235:genetics / Q000502:physiology; D009154:Mutation / Q000235:genetics; D019170:Somites / Q000378:metabolism*; D015027:Zebrafish / Q000235:genetics / Q000378:metabolism*; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D029961:Zebrafish Proteins; C107407:Mesp2 protein, mouse
keywords: Boundary formation; Mesp; Segmentation; Somitogenesis; TALEN; Zebrafish