title: Importance of region-specific epithelial rearrangements in mouse rugae development.
abstract: Epithelial appendages on palatal rugae develop during mouse palatogenesis through epithelial thickening and pattern formation. Recently, the patterned formation of nine rugae was observed together with the specific expression patterns of Shh in rodents. However, no crucial evidence was found for a direct association between Shh expression and the distinct structural formation of rugae. In order to reveal possible relationships, we investigated the morphological changes of rugae and expression patterns of Shh directly by in vitro organ culture at embryonic day 13 (E13) for 2 days. To compare and examine the diverse growing aspects of the palate and rugae, we carefully observed the detailed morphogenesis, with cell proliferation of the rugae occurring between E13 and E14.5. After 2 days of cultivation at E13, DiI micro-injections revealed that the middle part of the palate, adjacent to the upper molar-forming region, contributed to the formation of the subsequent structure of rugae by extensive cell rearrangement and proliferation within the epithelium in the preferred anteroposterior direction. The results also defined the intimate relationship between Shh expression and rugae formation.
authors.affiliation: School of Life Science and Biotechnology, Kyungpook National University, Daegu, Korea.
authors.forename: Wern-Joo
authors.initials: WJ
authors.lastname: Sohn
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Yamamoto
authors.forename: Hong-In
authors.initials: HI
authors.lastname: Shin
authors.forename: Zae Young
authors.initials: ZY
authors.lastname: Ryoo
authors.forename: Sanggyu
authors.initials: S
authors.lastname: Lee
authors.forename: Yong-Chul
authors.initials: YC
authors.lastname: Bae
authors.forename: Han-Sung
authors.initials: HS
authors.lastname: Jung
authors.forename: Jae-Young
authors.initials: JY
authors.lastname: Kim
mesh_terms: D000818:Animals; D004848:Epithelium / Q000196:embryology / Q000378:metabolism; D005260:Female; D053823:Hedgehog Proteins / Q000096:biosynthesis / Q000235:genetics; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D010159:Palate / Q000196:embryology* / Q000378:metabolism; D011247:Pregnancy
chemical_list: D053823:Hedgehog Proteins; C465570:Shh protein, mouse