title: Identification of a potent combination of osteogenic genes for bone regeneration using embryonic stem (ES) cell-based sensor.
abstract: To identify potent bioactive factors for in vivo tissue regeneration by comprehensive screening remains a challenge for regenerative medicine. Here we report the development of an ES cell-based monitoring system for osteogenic differentiation, the identification of a potent combination of osteogenic genes using such a system, and an evaluation of its therapeutic potentials. ES cells were isolated from mice carrying a transgene expressing GFP driven by the 2.3 kb fragment of rat type I collagen alpha1 promoter. Using these cells engineered to fluoresce on osteogenic differentiation, we screened cDNA libraries and combinations of major osteogenesis-related genes. Among them, the combination of constitutively active activin receptor-like kinase 6 (caALK6) and runt-related transcription factor 2 (Runx2) was the minimal unit that induced fluorescence. The combination efficiently induced osteogenic differentiation in various cell types, including terminally differentiated nonosteogenic cells. The cooperative action of the combination occurred through protein stabilization of core binding factor beta (Cbfb), induction of Runx2-Cbfb complex formation, and its DNA binding. Furthermore, transplantation of a monolayer sheet of fibroblasts transduced with the combination achieved bone regeneration within 4 wk in mouse calvarial bone defects. Thus, we successfully identified the potent combination of genes for bone regeneration, which helped broaden cell sources.
authors.affiliation: Japan Society for the Promotion of Science, Chiyoda-ku, Tokyo, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Ohba
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Ikeda
authors.forename: Fumitaka
authors.initials: F
authors.lastname: Kugimiya
authors.forename: Fumiko
authors.initials: F
authors.lastname: Yano
authors.forename: Alexander C
authors.initials: AC
authors.lastname: Lichtler
authors.forename: Kozo
authors.initials: K
authors.lastname: Nakamura
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Takato
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawaguchi
authors.forename: Ung-il
authors.initials: UI
authors.lastname: Chung
mesh_terms: D000818:Animals; D052005:Bone Morphogenetic Protein Receptors, Type I / Q000235:genetics / Q000502:physiology*; D001861:Bone Regeneration / Q000235:genetics*; D002454:Cell Differentiation; D050659:Core Binding Factor Alpha 1 Subunit / Q000235:genetics / Q000502:physiology*; D053595:Embryonic Stem Cells / Q000166:cytology*; D049452:Green Fluorescent Proteins / Q000235:genetics; D051379:Mice; D010012:Osteogenesis / Q000235:genetics*; D051381:Rats; D019076:Transgenes
chemical_list: D050659:Core Binding Factor Alpha 1 Subunit; C493716:Runx2 protein, mouse; D049452:Green Fluorescent Proteins; C498215:Bmpr1b protein, mouse; D052005:Bone Morphogenetic Protein Receptors, Type I