Degradation of enamelins by proteinases found in porcine secretory enamel in vitro.
The action of proteinases obtained from porcine secretory enamel on the porcine 89-kDa enamelin was examined in vitro. The results of sodium dodecyl sulphate-acrylamide gel electrophoresis of the reaction products indicated the following. (1) The 76- and 78-kDa proteinases localized in the outermost layer of the secretory enamel not only convert the 25-kDa amelogenin to the 20-kDa amelogenin, but also split the 89-kDa enamelin, which is the major enamelin component in the enamel in the very early secretory stage, into large fragments such as 25-, 41- and 56-kDa enamelins. (2) The serine proteinases localized in the inner layer of secretory enamel further degrade not only amelogenins but also enamelins.
Department of Biochemistry, School of Dental Medicine, Tsurumi University, Yokohama, Japan.
T
T
Tanabe
M
M
Fukae
M
M
Shimizu
D000566:Amelogenesis; D000818:Animals; D003743:Dental Enamel / Q000201:enzymology / Q000378:metabolism*; D003746:Dental Enamel Proteins / Q000378:metabolism*; D012697:Serine Endopeptidases / Q000502:physiology*; D013552:Swine
D003746:Dental Enamel Proteins; C038456:tuftelin; D012697:Serine Endopeptidases