title: Periostin is expressed within the developing teeth at the sites of epithelial-mesenchymal interaction.
abstract: Periostin was originally isolated as an osteoblast-specific factor that functions as a cell adhesion molecule for preosteoblasts and is thought to be involved in osteoblast recruitment, attachment, and spreading. The protein was renamed "periostin" because of its expression in the periosteum and periodontal ligament, indicating a potential role in bone and maintenance of tooth structure. Periostin has structural similarity to insect fasciclin-I and can be induced by TGF-beta and Bmp2. Because tooth and periodontium development is a well-described genetic model for organogenesis governed by a reciprocal set of epithelial-mesenchymal interactions, thought to be controlled by various TGF-beta superfamily members, we investigated whether periostin is present during tooth morphogenesis. Both periostin mRNA and protein expression were analyzed throughout normal tooth development (embryonic day [E] 9.5-newborn) and within both Bmp4- and Msx2-null embryos. Periostin mRNA is initially present within the E9.5 first branchial arch epithelium and then shifts to underlying ectomesenchyme. Both mRNA and protein are asymmetrically localized to the lingual/palatal and buccal side during the early epithelial-mesenchymal interactions. Periostin is also present in dental papilla cells and within the trans-differentiating odontoblasts during the bell and hard tissue formation stages of tooth development. We suggest that periostin plays multiple roles as a primary responder molecule during tooth development and may be linked to deposition and organization of other extracellular matrix adhesion molecules during maintenance of the adult tooth, particularly at the sites of hard-soft tissue interface.
authors.affiliation: Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, Georgia, USA.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Kruzynska-Frejtag
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.forename: Manabu
authors.initials: M
authors.lastname: Maeda
authors.forename: Rhonda
authors.initials: R
authors.lastname: Rogers
authors.forename: Edward
authors.initials: E
authors.lastname: Krug
authors.forename: Stanley
authors.initials: S
authors.lastname: Hoffman
authors.forename: Roger R
authors.initials: RR
authors.lastname: Markwald
authors.forename: Simon J
authors.initials: SJ
authors.lastname: Conway
mesh_terms: D000818:Animals; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins / Q000378:metabolism; D015815:Cell Adhesion Molecules / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism; D004622:Embryo, Mammalian / Q000378:metabolism; D004848:Epithelium / Q000196:embryology / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018398:Homeodomain Proteins / Q000378:metabolism; D017403:In Situ Hybridization; D051957:MSX1 Transcription Factor; D008648:Mesoderm / Q000378:metabolism; D051379:Mice; D008963:Molar / Q000378:metabolism; D009804:Odontoblasts / Q000378:metabolism; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis / Q000378:metabolism; D014070:Tooth / Q000033:anatomy & histology / Q000196:embryology* / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism
chemical_list: C525810:Bmp4 protein, mouse; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; D015815:Cell Adhesion Molecules; D004268:DNA-Binding Proteins; D018398:Homeodomain Proteins; D051957:MSX1 Transcription Factor; C084119:MSX2 protein; C082838:Postn protein, mouse; D020033:Protein Isoforms; D012333:RNA, Messenger; D014157:Transcription Factors