TY - JOUR
T1 - Runx1 is involved in the fusion of the primary and the secondary palatal shelves
AU - Charoenchaikorn, Kesinee
AU - Yokomizo, Tomomasa
AU - Rice, David P.
AU - Honjo, Tadashi
AU - Matsuzaki, Kiyomi
AU - Shintaku, Yuko
AU - Imai, Yuichi
AU - Wakamatsu, Asami
AU - Takahashi, Satoru
AU - Ito, Yoshiaki
AU - Takano-Yamamoto, Teruko
AU - Thesleff, Irma
AU - Yamamoto, Masayuki
AU - Yamashiro, Takashi
N1 - Funding Information:
We thank Dr. Clive Dickson and Dr. Bradley Spencer-Dene for Fgfr2b −/− mice. We thank Merja Mäkinen and Riikka Santalahti for their technical assistance. This work was supported by grants-in-aid for scientific research program from the Japan Society for the Promotion of Science (to T. Yamashiro).
PY - 2009/2/15
Y1 - 2009/2/15
N2 - Runx1 is expressed in medial edge epithelial (MEE) cells of the palatal shelf. Conditionally rescued Runx1-/- mice showed limited clefting in the anterior junction between the primary and the secondary palatal shelves, but not in the junction between the secondary palates. In wild type mice, the fusing epithelial surface exhibited a rounded cobblestone-like appearance, while such cellular prominence was less evident in the Runx1 mutants. We also found that Fgf18 was expressed in the mesenchyme underlying the MEE and that locally applied FGF18 induced ectopic Runx1 expression in the epithelium of the palatal explants, indicating that Runx1 was induced by mesenchymal Fgf18 signaling. On the other hand, unpaired palatal explant cultures revealed the presence of anterior-posterior (A-P) differences in the MEE fates and fusion mechanism. Interestingly, the location of anterior clefting in Runx1 mutants corresponded to the region with different MEE behavior. These data showed a novel function of Runx1 in morphological changes in the MEE cells in palatal fusion, which is, at least in part, regulated by the mesenchymal Fgf signaling via an epithelial-mesenchymal interaction.
AB - Runx1 is expressed in medial edge epithelial (MEE) cells of the palatal shelf. Conditionally rescued Runx1-/- mice showed limited clefting in the anterior junction between the primary and the secondary palatal shelves, but not in the junction between the secondary palates. In wild type mice, the fusing epithelial surface exhibited a rounded cobblestone-like appearance, while such cellular prominence was less evident in the Runx1 mutants. We also found that Fgf18 was expressed in the mesenchyme underlying the MEE and that locally applied FGF18 induced ectopic Runx1 expression in the epithelium of the palatal explants, indicating that Runx1 was induced by mesenchymal Fgf18 signaling. On the other hand, unpaired palatal explant cultures revealed the presence of anterior-posterior (A-P) differences in the MEE fates and fusion mechanism. Interestingly, the location of anterior clefting in Runx1 mutants corresponded to the region with different MEE behavior. These data showed a novel function of Runx1 in morphological changes in the MEE cells in palatal fusion, which is, at least in part, regulated by the mesenchymal Fgf signaling via an epithelial-mesenchymal interaction.
KW - Anterior clefting
KW - Cleft palate
KW - Epithelial fusion
KW - Epithelial-mesenchymal interactions
KW - Fgf18
KW - Palatal explants
KW - Palatogenesis
KW - Primary palate
KW - Runx1
KW - Secondary palate
UR - http://www.scopus.com/inward/record.url?scp=58749095272&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=58749095272&partnerID=8YFLogxK
U2 - 10.1016/j.ydbio.2008.10.018
DO - 10.1016/j.ydbio.2008.10.018
M3 - Article
C2 - 19000669
AN - SCOPUS:58749095272
SN - 0012-1606
VL - 326
SP - 392
EP - 402
JO - Developmental Biology
JF - Developmental Biology
IS - 2
ER -