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.
Tanabe
T
T
Department of Biochemistry, School of Dental Medicine, Tsurumi University, Yokohama, Japan.
Fukae
M
M
Shimizu
M
M
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