title: Expression of Clu and Tgfb1 during murine tooth development: effects of in-vivo transfection with anti-miR-214.
abstract: Expression of clusterin (Clu) in the murine first molar tooth germ was markedly increased at postnatal developmental stages. The time-course of expression of this gene paralleled those of other genes encoding proteins involved during the secretory phase of odontogenesis, as described previously. Immunohistochemical studies of clusterin in murine molar tooth germs suggested this protein to be located in outer enamel epithelium, regressing enamel organ, secretory ameloblasts, and the dental epithelium connecting the tooth to the oral epithelium at an early eruptive stage. Immunolabelling of transforming growth factor beta-1 (TGF-β1) revealed it to be located close to clusterin. The levels of expression of Clu and Tgfb1 were markedly decreased following in-vivo transfection with anti-miR-214. In contrast, the expression of several genes associated with regulation of growth and development were increased by this treatment. We suggest that clusterin has functions during secretory odontogenesis and the early eruptive phase. Bioinformatic analysis after treatment with anti-miR-214 suggested that, whilst cellular activities associated with tooth mineralization and eruption were inhibited, activities associated with an alternative developmental activity (i.e. biosynthesis of contractile proteins) appeared to be stimulated. These changes probably occur through regulation mediated by a common cluster of transcription factors and support suggestions that microRNAs (miRNAs) are highly significant as regulators of differentiation during odontogenesis.
authors.affiliation: Department of Oral Biology, University of Oslo, Oslo, Norway. qsahmed@odont.uio.no
authors.forename: Qalb-E-Saleem
authors.initials: QE
authors.lastname: Khan
authors.forename: Amer
authors.initials: A
authors.lastname: Sehic
authors.forename: Cuong
authors.initials: C
authors.lastname: Khuu
authors.forename: Steinar
authors.initials: S
authors.lastname: Risnes
authors.forename: Harald
authors.initials: H
authors.lastname: Osmundsen
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D051152:Clusterin / Q000032:analysis / Q000235:genetics*; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D007150:Immunohistochemistry; D051379:Mice; D035683:MicroRNAs / Q000037:antagonists & inhibitors*; D008963:Molar / Q000196:embryology / Q000254:growth & development*; D009805:Odontogenesis / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014074:Tooth Calcification / Q000235:genetics*; D014083:Tooth Germ / Q000196:embryology / Q000254:growth & development* / Q000378:metabolism; D014162:Transfection; D053773:Transforming Growth Factor beta1 / Q000032:analysis / Q000235:genetics*
chemical_list: D051152:Clusterin; D035683:MicroRNAs; C534781:Mirn214 microRNA, mouse; D053773:Transforming Growth Factor beta1
keywords: clusterin; eruption; miR-214; mouse molar; transforming growth factor beta-1