title: Synaptic vesicle protein 2b is expressed temporospatially in (pre)odontoblasts in developing molars.
abstract: The formation of dentin and enamel is initiated by the differentiation of odontogenic precursor cells into odontoblasts and ameloblasts, respectively. This study was performed to identify new molecules involved in the differentiation of odontogenic cells. The genes expressed differentially between the root stage (after the differentiation of odontogenic cells and dental hard-tissue formation) and the cap stage (before the differentiation of odontogenic cells and dental hard-tissue formation) were searched using differential display PCR. For the first time, synaptic vesicle protein (SV) 2b, an important transmembrane transporter of Ca(2+) -stimulated vesicle exocytosis, was identified as a differentially expressed molecule. Real-time PCR and western blotting revealed an increase in the transcriptional and translational levels of SV2b during or after the differentiation of odontogenic cells. Immunofluorescence revealed this molecule to be localized in not only fully differentiated odontoblasts but also in pre-odontoblasts before dentin matrix secretion. The expression pattern of the SV2a isoform was similar to that of the SV2b isoform, whereas the SV2c isoform showed a contrasting pattern of expression. After treatment with alendronate, an inhibitor of protein isoprenylation for the transport of secretory vesicles, the expression of SV2a and SV2b decreased, whereas that of SV2c increased. These results suggest that the SV2 isoforms are functional molecules of (pre)odontoblasts which may be involved in vesicle transport.
authors.affiliation: Dental Science Research Institute, 2nd stage Brain Korea, School of Dentistry, Chonnam National University, Gwangju, South Korea.
authors.forename: So-Young
authors.initials: SY
authors.lastname: Yang
authors.forename: Soo-Kyung
authors.initials: SK
authors.lastname: Jeon
authors.forename: Jee-Hae
authors.initials: JH
authors.lastname: Kang
authors.forename: Hong-Il
authors.initials: HI
authors.lastname: Yoo
authors.forename: Yoo-Seong
authors.initials: YS
authors.lastname: Kim
authors.forename: Jung-Sun
authors.initials: JS
authors.lastname: Moon
authors.forename: Min-Seok
authors.initials: MS
authors.lastname: Kim
authors.forename: Jung-Tae
authors.initials: JT
authors.lastname: Koh
authors.forename: Won-Mann
authors.initials: WM
authors.lastname: Oh
authors.forename: Sun-Hun
authors.initials: SH
authors.lastname: Kim
mesh_terms: D019386:Alendronate / Q000378:metabolism; D000818:Animals; D002454:Cell Differentiation / Q000235:genetics*; D005089:Exocytosis / Q000235:genetics*; D005786:Gene Expression Regulation; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000378:metabolism; D009804:Odontoblasts / Q000166:cytology / Q000378:metabolism*; D009805:Odontogenesis / Q000235:genetics* / Q000502:physiology; D020033:Protein Isoforms / Q000235:genetics; D059368:RNA Isoforms / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D013572:Synaptic Vesicles / Q000378:metabolism*; D014083:Tooth Germ / Q000166:cytology* / Q000378:metabolism
chemical_list: D008562:Membrane Glycoproteins; D009419:Nerve Tissue Proteins; D020033:Protein Isoforms; D059368:RNA Isoforms; C489617:Sv2b protein, rat; D019386:Alendronate