title: Dentin sialoprotein (DSP) transcripts: developmentally-sustained expression in odontoblasts and transient expression in pre-ameloblasts.
abstract: Dentin sialoprotein (DSP), a 53 kDa glycoprotein, is believed to be present exclusively in dentin. Using rat and mouse digoxigenin labeled (DIG)-DSP and 35S-DSP riboprobes, and in situ hybridization techniques, we have studied the presence of DSP mRNA at specific developmental stages of dentinogenesis. In mouse and rat molars and incisors, DSP transcripts were localized in young odontoblasts associated with early stages of predentin formation, as well as in mature odontoblasts, cells with cytoplasmic extensions embedded in the forming dentin. No DSP transcripts were detected in dental pulp, enamel organ, ameloblasts, epithelial root sheath, Meckel's cartilage, alveolar bone or tibia. Furthermore, no DSP mRNA was observed in other soft tissues including heart, lung, kidney, intestine, eye, and muscle. In addition to the intense and prolonged expression by odontoblasts, DSP mRNA was transiently expressed by pre-ameloblasts in both developing molars and incisors. These observations are consistent with the results of previous immunohistochemical studies (1). The transient expression of DSP in pre-ameloblasts across from young odontoblasts suggests an involvement of DSP in epithelial-mesenchymal interactions that are crucial to later stages of tooth development.
authors.affiliation: Department of Basic Sciences, University of Texas-Houston Health Science Center, Dental Branch, 77030, USA. helena-ritchie@uiowa.edu
authors.forename: H H
authors.initials: HH
authors.lastname: Ritchie
authors.forename: J E
authors.initials: JE
authors.lastname: Berry
authors.forename: M J
authors.initials: MJ
authors.lastname: Somerman
authors.forename: C T
authors.initials: CT
authors.lastname: Hanks
authors.forename: A L
authors.initials: AL
authors.lastname: Bronckers
authors.forename: D
authors.initials: D
authors.lastname: Hotton
authors.forename: P
authors.initials: P
authors.lastname: Papagerakis
authors.forename: A
authors.initials: A
authors.lastname: Berdal
authors.forename: W T
authors.initials: WT
authors.lastname: Butler
mesh_terms: D000539:Alveolar Process / Q000378:metabolism; D000565:Ameloblasts / Q000378:metabolism*; D000818:Animals; D002356:Cartilage / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D003782:Dental Pulp / Q000378:metabolism; D003804:Dentin / Q000378:metabolism; D003810:Dentinogenesis / Q000235:genetics; D004076:Digoxigenin; D004658:Enamel Organ / Q000378:metabolism; D004848:Epithelium / Q000378:metabolism; D016326:Extracellular Matrix Proteins; D018507:Gene Expression Regulation, Developmental; D017403:In Situ Hybridization; D007180:Incisor; D008334:Mandible / Q000378:metabolism; D008648:Mesoderm / Q000378:metabolism; D051379:Mice; D008815:Mice, Inbred Strains; D008963:Molar; D009804:Odontoblasts / Q000378:metabolism*; D009805:Odontogenesis / Q000235:genetics; D010750:Phosphoproteins; D011498:Protein Precursors; D015347:RNA Probes; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D012795:Sialoglycoproteins / Q000235:genetics*; D013977:Tibia / Q000378:metabolism; D014083:Tooth Germ / Q000378:metabolism; D014092:Tooth Root / Q000378:metabolism; D014158:Transcription, Genetic; D000099311:Dentin Sialophosphoprotein
chemical_list: D004076:Digoxigenin; D016326:Extracellular Matrix Proteins; D010750:Phosphoproteins; D011498:Protein Precursors; D015347:RNA Probes; D012333:RNA, Messenger; D012795:Sialoglycoproteins; D000099311:Dentin Sialophosphoprotein