title: MMP2-cleavage of DMP1 generates a bioactive peptide promoting differentiation of dental pulp stem/progenitor cell.
abstract: Dentin Matrix Protein 1 (DMP1) plays a regulatory role in dentin mineralization and can also function as a signaling molecule. MMP-2 (matrix metalloproteinase-2) is a predominant protease in the dentin matrix that plays a prominent role in tooth formation and a potential role during the carious process. The possibility that MMP-2 can cleave DMP1 to release biologically active peptides was investigated in this study. DMP1, both in the recombinant form and in its native state within the dentin matrix, was shown to be a substrate for MMP-2. Proteolytic processing of DMP1 by MMP-2 produced two major peptides, one that contains the C-terminal region of the protein known to carry both the ASARM (aspartic acid and serine rich domain) domain involved in biomineralization and the DNA binding site of DMP1. In vitro experiments with recombinant N- and C-terminal polypeptides mimicking the MMP-2 cleavage products of DMP1 demonstrated an effect of the C-polypeptide on the differentiation of dental pulp stem/progenitor cells to a putative odontoblast phenotype. In vivo implantation of this peptide in a rat injured pulp model induced a rapid formation of a homogeneous dentin bridge covered by a palisade of orientated cells expressing dentin sialoprotein (DSP) and DMP1, attesting an efficient repair process. These data suggest that a peptide generated through the proteolytic processing of DMP1 by MMP-2 can regulate the differentiation of mesenchymal cells during dentinogenesis and thus sustain reparative dentin formation in pathological situations such as carious decay. In addition, these data open a new therapeutic possibility of using this peptide to regenerate dentin after an injury.
authors.affiliation: Department of Oral Biology, University of Illinois, Chicago, IL 60612, USA. catherine.chaussain@parisdescartes.fr
authors.forename: Catherine
authors.initials: C
authors.lastname: Chaussain
authors.forename: Asha Sarah
authors.initials: AS
authors.lastname: Eapen
authors.forename: Eric
authors.initials: E
authors.lastname: Huet
authors.forename: Caroline
authors.initials: C
authors.lastname: Floris
authors.forename: Sriram
authors.initials: S
authors.lastname: Ravindran
authors.forename: Jianjun
authors.initials: J
authors.lastname: Hao
authors.forename: Suzanne
authors.initials: S
authors.lastname: Menashi
authors.forename: Anne
authors.initials: A
authors.lastname: George
mesh_terms: D000328:Adult; D000595:Amino Acid Sequence; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects*; D003782:Dental Pulp / Q000166:cytology*; D003810:Dentinogenesis / Q000235:genetics; D016326:Extracellular Matrix Proteins / Q000378:metabolism* / Q000502:physiology; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000502:physiology; D010750:Phosphoproteins / Q000378:metabolism* / Q000502:physiology; D051381:Rats; D011994:Recombinant Proteins / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology / Q000502:physiology*
chemical_list: C081635:Dmp1 protein, rat; D016326:Extracellular Matrix Proteins; D010446:Peptide Fragments; D010750:Phosphoproteins; D011994:Recombinant Proteins; D020778:Matrix Metalloproteinase 2