HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 282, Issue 8, 5340-5345, February 23, 2007

This Article Full Text Full Text (PDF) All Versions of this Article: 282/8/5340    most recent M604814200v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by White, S. N. Articles by Snead, M. L. Search for Related Content PubMed PubMed Citation Articles by White, S. N. Articles by Snead, M. L. Social Bookmarking                      What's this?

Ectopic Expression of Dentin Sialoprotein during Amelogenesis Hardens Bulk Enamel^*

Shane N. White, Michael L. Paine¹, Amanda Y. W. Ngan, Vetea G. Miklus, Wen Luo, HongJun Wang, and Malcolm L. Snead

From the School of Dentistry, University of California at Los Angeles, Los Angeles, California, 90095 and School of Dentistry, Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, California 90033

Dentin sialophosphpoprotein (Dspp) is transiently expressed in the early stage of secretory ameloblasts. The secretion of ameloblast-derived Dspp is short-lived, correlates to the establishment of the dentinoenamel junction (DEJ), and is consistent with Dspp having a role in producing the specialized first-formed harder enamel adjacent to the DEJ. Crack diffusion by branching and dissipation within this specialized first-formed enamel close to the DEJ prevents catastrophic interfacial damage and tooth failure. Once Dspp is secreted, it is subjected to proteolytic cleavage that results in two distinct proteins referred to as dentin sialoprotein (Dsp) and dentin phosphoprotein (Dpp). The purpose of this study was to investigate the biological and mechanical contribution of Dsp and Dpp to enamel formation. Transgenic mice were engineered to overexpress either Dsp or Dpp in their enamel organs. The mechanical properties (hardness and toughness) of the mature enamel of transgenic mice were compared with genetically matched and age-matched nontransgenic animals. Dsp and Dpp contributions to enamel formation greatly differed. The inclusion of Dsp in bulk enamel significantly and uniformly increased enamel hardness (20%), whereas the inclusion of Dpp weakened the bulk enamel. Thus, Dsp appears to make a unique contribution to the physical properties of the DEJ. Dsp transgenic animals have been engineered with superior enamel mechanical properties.

Received for publication, May 18, 2006 , and in revised form, November 6, 2006.

^* This work was supported by Grants DE013045, DE013404, and DE014189 from the NIDCR, National Institutes of Health. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

¹ To whom correspondences should be addressed: Univ. of Southern California, School of Dentistry, Center for Craniofacial Molecular Biology, 2250 Alcazar St., CSA Rm. 142, Los Angeles, CA 90033. Ph.: 323-442-1728; Fax: 323-442-2981; E-mail: paine{at}usc.edu.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				Y. Li, C. Suggs, J. T. Wright, Z.-a. Yuan, M. Aragon, H. Fong, D. Simmons, B. Daly, E. E. Golub, G. Harrison, et al. Partial Rescue of the Amelogenin Null Dental Enamel Phenotype J. Biol. Chem., May 30, 2008; 283(22): 15056 - 15062. [Abstract] [Full Text] [PDF]

				M.L. Paine, M.L. Snead, H.J. Wang, N. Abuladze, A. Pushkin, W. Liu, L.Y. Kao, S.M. Wall, Y.-H. Kim, and I. Kurtz Role of NBCe1 and AE2 in Secretory Ameloblasts J. Dent. Res., April 1, 2008; 87(4): 391 - 395. [Abstract] [Full Text] [PDF]