Transgenic overexpression of gremlin results in developmental defects in enamel and dentin in mice.
Bone morphogenetic proteins (BMPs) and BMP antagonists play a crucial role in the regulation of tooth development. One of the BMP extracellular antagonists, gremlin, is a highly conserved 20.7-kDa glycoprotein. Previously, researchers reported that transgenic mice overexpressing gremlin under the control of the osteocalcin promoter (gremlin OE) exhibit a skeletal phenotype and tooth fragility. To further define the tooth phenotype, teeth and surrounding supporting tissues, obtained from gremlin OE at ages of 4 weeks, 2 months, and 4 months, were examined. The histological results demonstrate that gremlin OE exhibit an enlarged pulp chamber with ectopic calcification and thinner dentin and enamel compared with wild-type control. In vitro studies using murine pulp cells revealed that gremlin inhibited BMP-4 mediated induction of Dspp. These data provide evidence that balanced interactions between BMP agonists/antagonists are required for proper development of teeth and surrounding tissues. It is clear that these interactions require further investigation to better define the mechanisms controlling tooth root formation (pulp, dentin, cementum, and surrounding tissue) to provide the information needed to successfully regenerate these tissues.
Nagatomo
Kanako J
KJ
Department of Periodontics, School of Dentistry, [corrected] University of Washington, Seattle, Washington, USA.
Tompkins
Kevin A
KA
Fong
Hanson
H
Zhang
Hai
H
Foster
Brian L
BL
Chu
Emily Y
EY
Murakami
Ayu
A
Stadmeyer
Lisa
L
Canalis
Ernesto
E
Somerman
Martha J
MJ
D000818:Animals; D055415:Bone Morphogenetic Protein 4 / Q000378:metabolism*; D016207:Cytokines; D003743:Dental Enamel / Q000002:abnormalities* / Q000378:metabolism; D003782:Dental Pulp / Q000166:cytology / Q000648:ultrastructure; D003804:Dentin / Q000002:abnormalities* / Q000378:metabolism; D016326:Extracellular Matrix Proteins; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D008855:Microscopy, Electron, Scanning; D009805:Odontogenesis / Q000235:genetics; D010750:Phosphoproteins; D011498:Protein Precursors / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D051381:Rats; D012795:Sialoglycoproteins; D014074:Tooth Calcification / Q000235:genetics; D000099311:Dentin Sialophosphoprotein
D055415:Bone Morphogenetic Protein 4; D016207:Cytokines; D016326:Extracellular Matrix Proteins; D036341:Intercellular Signaling Peptides and Proteins; D010750:Phosphoproteins; D011498:Protein Precursors; D012795:Sialoglycoproteins; D000099311:Dentin Sialophosphoprotein; C525810:Bmp4 protein, mouse; C113178:Grem1 protein, mouse