title: Acute transcriptional up-regulation specific to osteoblasts/osteoclasts in medaka fish immediately after exposure to microgravity.
abstract: Bone loss is a serious problem in spaceflight; however, the initial action of microgravity has not been identified. To examine this action, we performed live-imaging of animals during a space mission followed by transcriptome analysis using medaka transgenic lines expressing osteoblast and osteoclast-specific promoter-driven GFP and DsRed. In live-imaging for osteoblasts, the intensity of osterix- or osteocalcin-DsRed fluorescence in pharyngeal bones was significantly enhanced 1 day after launch; and this enhancement continued for 8 or 5 days. In osteoclasts, the signals of TRAP-GFP and MMP9-DsRed were highly increased at days 4 and 6 after launch in flight. HiSeq from pharyngeal bones of juvenile fish at day 2 after launch showed up-regulation of 2 osteoblast- and 3 osteoclast- related genes. Gene ontology analysis for the whole-body showed that transcription of genes in the category "nucleus" was significantly enhanced; particularly, transcription-regulators were more up-regulated at day 2 than at day 6. Lastly, we identified 5 genes, c-fos, jun-B-like, pai-1, ddit4 and tsc22d3, which were up-regulated commonly in the whole-body at days 2 and 6, and in the pharyngeal bone at day 2. Our results suggested that exposure to microgravity immediately induced dynamic alteration of gene expression levels in osteoblasts and osteoclasts.
authors.affiliation: Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Chatani
authors.affiliation: Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan.
authors.forename: Hiroya
authors.initials: H
authors.lastname: Morimoto
authors.affiliation: Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Takeyama
authors.affiliation: Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Mantoku
authors.affiliation: Chiyoda Corporation, Yokohama 220-8765, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Tanigawa
authors.affiliation: Chiyoda Corporation, Yokohama 220-8765, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Kubota
authors.affiliation: Department of Science and Applications, Japan Space Forum, Tokyo 101-0062, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Suzuki
authors.affiliation: Department of Science and Applications, Japan Space Forum, Tokyo 101-0062, Japan.
authors.forename: Satoko
authors.initials: S
authors.lastname: Uchida
authors.affiliation: Japan Aerospace Exploration Agency, Tsukuba 305-8505, Japan.
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Tanigaki
authors.affiliation: Japan Aerospace Exploration Agency, Tsukuba 305-8505, Japan.
authors.forename: Masaki
authors.initials: M
authors.lastname: Shirakawa
authors.affiliation: Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan 420008, Russia.
authors.forename: Oleg
authors.initials: O
authors.lastname: Gusev
authors.affiliation: SSC RF-Institute of Biomedical Problems RAS, Moscow, Russia.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Sychev
authors.affiliation: Section of Biostructural Science, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo 113-8549, Japan.
authors.forename: Yoshiro
authors.initials: Y
authors.lastname: Takano
authors.affiliation: Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan.
authors.forename: Takehiko
authors.initials: T
authors.lastname: Itoh
authors.affiliation: Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama 226-8501, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Kudo
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001842:Bone and Bones / Q000378:metabolism; D005399:Fishes; D015870:Gene Expression; D005786:Gene Expression Regulation; D008164:Luminescent Proteins / Q000737:chemistry; D009990:Oryzias / Q000235:genetics; D010006:Osteoblasts / Q000166:cytology* / Q000378:metabolism; D015675:Osteocalcin / Q000378:metabolism; D010010:Osteoclasts / Q000166:cytology* / Q000378:metabolism; D013026:Space Flight; D014158:Transcription, Genetic; D059467:Transcriptome; D015854:Up-Regulation; D014893:Weightlessness
chemical_list: D008164:Luminescent Proteins; C413663:fluorescent protein 583; D015675:Osteocalcin