Calmodulin-like activity in a mineralising tissue: the rat molar tooth germ.

Abstract

Calmodulin, a calcium binding protein, has been implicated in the regulation of many calcium-dependent biological processes. Since calcium has an important role in hard tissue genesis, both at intra- and extracellular levels, we anticipate that calcium binding proteins may modulate this process. The present study investigated a mineralising tissue, the rat molar tooth germ, to determine the presence of calmodulin-like activity. A heat-treated cell-free extract of tooth germs provided enhancement of Ca2+-dependent Mg2+-ATPase and 3':5'-nucleotide phosphodiesterase activity. No enhancement occurred in the absence of calcium or in the presence of trifluoperazine. SDS-polyacrylamide gel electrop..