Journal of Dental Research, Vol 75, 1381-1387, Copyright © 1996 by International & American Associations for Dental Research Online Journals
Electrophoretic gels of dentin matrix proteins as diffusion media for in vitro mineralization
Y. Wada, R. Fujisawa, Y. Nodasaka and Y. Kuboki
Department of Biochemistry, Hokkaido University, Sapporo, Japan.
Non-collagenous proteins of dentin and bone have important effects on
mineralization which have been studied by various in vitro systems. We
developed an in vitro mineralization system using electrophoretic gels as
diffusion media of calcium and phosphate ions. Calcium and phosphate ions
were diffused naturally or propelled by electric potential. Calcium
phosphate was precipitated in the gel, and the precipitation was affected
by proteins in the gel which had been separated by electrophoresis. We
applied this system to analysis of non-collagenous proteins of dentin.
Among the proteins, phosphophoryns promoted calcium phosphate precipitation
in the natural-diffusion system. A non-collagenous protein having a
molecular mass of 60 kDa inhibited precipitation. The results were
different, however, in the electric-diffusion system, in which
phosphophoryns had a negative effect. The present system enabled us to
compare the effects of plural proteins rapidly, even using unpurified
material.
