Ultramicrostructural analysis of biomineralization processes of DMP1

2014 Fiscal Year Final Research Report

• Project/Area Number: 24390409
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Morphological basic dentistry
• Research Institution: Osaka University
• Principal Investigator: TOYOSAWA Satoru 大阪大学, 歯学研究科(研究院), 教授 (30243249)
• Co-Investigator(Kenkyū-buntansha): YASUDA Hidehiro 大阪大学, 学内共同利用施設, 教授 (60210259) ; MIURA Ichirou 大阪大学, 歯学部附属病院, 助教 (70437383) ; ISHIMOTO Takuya 大阪大学, 工学研究科, 助教 (50508835) ; SAEKI Makio 大阪大学, 工学研究科, 助教 (30273692) ; USA Yu 大阪大学, 歯学部附属病院, 助教 (80444579)
• Co-Investigator(Renkei-kenkyūsha): KAGAWA Ryousuke 大阪大学, 歯学部附属病院, 医員 (40448147)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 生体内石灰化 / dentin matrix protein 1 / 翻訳後修飾 / 超微構造 / 骨細胞

Outline of Final Research Achievements

DMP1 (dentin matrix protein 1) is a non-collagenous matrix protein produced by osteocytes buried in bone matrix. DMP1 has a large number of phosphorylation sites and these regions become highly negative-charged domain after phosphorylation. The highly phosphorylated, negative-charged DMP1 may play an important role in the bone mineralization by recruiting Ca2+ and subsequent mineral deposition. In this study, ultramicrostructural analysis suggested DMP1 did not participate in initial calcification in the osteoid. Immunohistochemical analysis suggested after post-translational cleavage, DMP1 had a tendency to be localized at perilacunar matrix as an NH2-terminal fragment and at pericanalicular matrix as a COOH-terminal fragment. Further, COOH-terminal fragment at pericanalicular matrix was demonstrated to be highly phosphorylated. Therefore, highly phosphorylated, negative-charged COOH-terminal fragment at pericanalicular matrix may play an important role in the bone mineralization.

Free Research Field

口腔病理学