| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Department of Orthodontics and Pediatric Dentistry and 2 Department of Biologic and Materials Science, University of Michigan, School of Dentistry, 1011 North University, Ann Arbor, MI 48109-1078, USA;
* corresponding author, University of Michigan Dental Research Laboratory, 1210 Eisenhower Place, Ann Arbor, MI 48108, USA; janhu{at}umich.edu
Dental enamel forms as a progressively thickening extracellular layer by the action of proteins secreted by ameloblasts. The most abundant enamel protein is amelogenin, which is expressed primarily from a gene on the X-chromosome (AMELX). The two most abundant non-amelogenin enamel proteins are ameloblastin and enamelin, which are expressed from the AMBN and ENAM genes, respectively. The human AMBN and ENAM genes are located on chromosome 4q13.2. The major secretory products of the human AMELX, AMBN, and ENAM genes have 175, 421, and 1103 amino acids, respectively, and are all post-translationally modified, secreted, and processed by proteases. Mutations in AMELX have been shown to cause X-linked amelogenesis imperfecta (AI), which accounts for 5% of AI cases. Mutations in ENAM cause a severe form of autosomal-dominant smooth hypoplastic AI that represents 1.5%, and a mild form of autosomal-dominant local hypoplastic AI that accounts for 27% of AI cases in Sweden. The discovery of mutations in the ENAM gene in AI kindreds proved that enamelin is critical for proper dental enamel formation and that it plays a role in human disease. Here we review how enamelin was discovered, what is known about enamelin protein structure, post-translational modifications, processing by proteases, and its potentially important functional properties such as its affinity for hydroxyapatite and influence on crystal growth in vitro. The primary structures of human, porcine, mouse, and rat enamelin are compared, and the human enamelin gene, its structure, chromosomal localization, temporal and spatial patterns of expression, and its role in the etiology of amelogenesis imperfecta are discussed.
Key words. Enamel, enamelin, amelogenin, ameloblastin, amelogenesis imperfecta, biomineralization, tooth formation
This article has been cited by other articles:
|
|
 |
|
  K. Kawasaki and K.M. Weiss SCPP Gene Evolution and the Dental Mineralization Continuum J. Dent. Res., June 1, 2008; 87(6): 520 - 531. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. C.-C. Hu, Y. Hu, C. E. Smith, M. D. McKee, J. T. Wright, Y. Yamakoshi, P. Papagerakis, G. K. Hunter, J. Q. Feng, F. Yamakoshi, et al. Enamel Defects and Ameloblast-specific Expression in Enam Knock-out/lacZ Knock-in Mice J. Biol. Chem., April 18, 2008; 283(16): 10858 - 10871. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. L. Kelley and W. J. Swanson Dietary Change and Adaptive Evolution of enamelin in Humans and Among Primates Genetics, March 1, 2008; 178(3): 1595 - 1603. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H.C. Margolis, E. Beniash, and C.E. Fowler Role of Macromolecular Assembly of Enamel Matrix Proteins in Enamel Formation J. Dent. Res., September 1, 2006; 85(9): 775 - 793. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. Ozdemir, P.S. Hart, E. Firatli, G. Aren, O.H. Ryu, and T.C. Hart Phenotype of ENAM Mutations is Dosage-dependent J. Dent. Res., November 1, 2005; 84(11): 1036 - 1041. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J.-W. Kim, F. Seymen, B.P.-J. Lin, B. Kiziltan, K. Gencay, J.P. Simmer, and J.C.-C. Hu ENAM Mutations in Autosomal-dominant Amelogenesis Imperfecta J. Dent. Res., March 1, 2005; 84(3): 278 - 282. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J-W Kim, J P Simmer, T C Hart, P S Hart, M D Ramaswami, J D Bartlett, and J C-C Hu MMP-20 mutation in autosomal recessive pigmented hypomaturation amelogenesis imperfecta J. Med. Genet., March 1, 2005; 42(3): 271 - 275. [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| IADR Journals | Advances in Dental Research ® | Journal of Dental Research ® | Critical Reviews (1990-2004) |
