[Expression patterns of amelogenin and enamelin in developing mouse tooth germs].
OBJECTIVE
To invesitgate the expression patterns of amelogenin and enamelin in the developing tooth germs.


METHODS
Mandible sections of postnatal day 1, 3, 7 and 14 mouse were prepared, immunohistochemical analysis and reverse transcriptase polymerase chain reaction (RT-PCR) were performed to detect the expression patterns of amelogenin and enamelin in mandibular first molars.


RESULTS
Amelogenin was observed in the cytoplasm of secretory ameloblasts and the whole enamel matrix layer. It was also transiently expressed in the odontoblasts of postnatal day 1 molars. Enamelin proteins were observed in the enamel layer deposited by secretory ameloblasts, especially intense beneath the ameloblast process and dentino-enamel junction. The mRNA levels of both amelogenin and enamelin were highest on postnatal day 7 (the ratio to glyceraldehyde phosphate dehydrogenase of amelogenin and enamelin: 0.813 ± 0.085 and 0.799 ± 0.064, respectively, P < 0.05).


CONCLUSIONS
Amelogenin and enamelin were enamel matrix proteins predominately expressed by secretory ameloblasts. The temporal-spatial expression patterns of amelogenin and enamelin indicate the important roles they played in amelogenesis and biomineralization.
Department of Cariology and Endodontology, Peking University School and Hospital of Stomatology, Beijing 100081, China.
Hua
H
Tian
Ping
P
Lü
Chun-yan
CY
Zhou
Xue-jun
XJ
Gao
D000565:Ameloblasts / Q000378:metabolism; D000566:Amelogenesis; D053523:Amelogenin / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D003743:Dental Enamel / Q000378:metabolism; D003746:Dental Enamel Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D008813:Mice, Inbred ICR; D008963:Molar / Q000378:metabolism; D009804:Odontoblasts / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D013997:Time Factors; D014083:Tooth Germ / Q000254:growth & development* / Q000378:metabolism
D053523:Amelogenin; D003746:Dental Enamel Proteins; D012333:RNA, Messenger; C038456:tuftelin