Gelatinase A (MMP-2) in developing tooth tissues and amelogenin hydrolysis.
Matrix metalloproteinases (MMPs) are thought to play important roles during enamel and dentin biomineralization. Previously, membrane type-1 matrix metalloproteinase (MT1-MMP) was localized to the plasma membranes of ameloblasts and odontoblasts of the developing tooth. The best-characterized function of MT1-MMP is to initiate the activation of gelatinase A (MMP-2). Thus, we hypothesized that gelatinase A may also be expressed by developing tooth tissues. A full-length porcine gelatinase A mRNA was isolated by RT-PCR homology cloning of an enamel-organ-specific cDNA library. Northern blot and in situ hybridization analyses demonstrated gelatinase A expression in developing tooth tissues. Immunohistochemical analysis localized gelatinase A close to the plasma membrane of these tissues. Furthermore, recombinant gelatinase A was demonstrated to cleave recombinant amelogenin into several fragments of differing molecular masses. Thus, gelatinase A is expressed by developing tooth tissues along with its activator MT1-MMP and may, therefore, play an important role during tooth development.
Caron
C
C
Laval University, Faculty of Dentistry, Quebec, Canada.
Xue
J
J
Sun
X
X
Simmer
J P
JP
Bartlett
J D
JD
D000565:Ameloblasts / Q000378:metabolism; D053523:Amelogenin; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003746:Dental Enamel Proteins / Q000378:metabolism*; D003771:Dental Papilla / Q000378:metabolism*; D004658:Enamel Organ / Q000378:metabolism*; D006801:Humans; D006868:Hydrolysis; D020778:Matrix Metalloproteinase 2 / Q000096:biosynthesis* / Q000737:chemistry; D053504:Matrix Metalloproteinases, Membrane-Associated; D008666:Metalloendopeptidases / Q000096:biosynthesis; D008969:Molecular Sequence Data; D009804:Odontoblasts / Q000378:metabolism; D009805:Odontogenesis / Q000502:physiology*; D013552:Swine
D053523:Amelogenin; D003746:Dental Enamel Proteins; D053504:Matrix Metalloproteinases, Membrane-Associated; D008666:Metalloendopeptidases; D020778:Matrix Metalloproteinase 2