Association of Shh and Ptc with keratin localization in the initiation of the formation of circumvallate papilla and von Ebner's gland.
The development of gustatory papillae in mammalian embryos requires the coordination of a series of morphological events, such as proliferation, differentiation and innervation. In mice, the circumvallate papilla (CVP) is a specialized structure that develops in a characteristic spatial and temporal pattern in the posterior region of the tongue dorsal surface. The distinct expression patterns of Shh and Ptc, which play important roles in the development of other epithelial appendages, have been localized in the trench wall that gives rise to von Ebner's gland (VEG). To define the cellular mechanisms responsible for morphogenesis and differentiation during early development of CVP and VEG, the localization patterns of keratins (cytokeratins) K7, K8, K18, K19, K14 and connexin-43, which are dependent on Shh expression in other developmental systems, have been examined in detail. The distinct localization of keratins K7, K8, K18, K19, K14 and connexin-43 in the epithelium giving rise to the CVP and VEG suggests that cytodifferentiation is established prior to morphological changes. Interestingly, the localization of proliferating cell nuclear antigen, a marker for cell proliferation, is similar to that of Shh. An understanding of the regulatory roles of cell-cell interactions and signalling molecules in orchestrating a mutual network will bring us nearer to defining the molecular and cellular mechanisms underlying morphogenesis in mammalian taste bud development.
Division in Anatomy, Developmental Biology, Research Center for Orofacial Hard Tissue Regeneration, Oral Science Research Center, College of Dentistry, Yonsei Center of Biotechnology, Yonsei University, Seoul, South Korea.
Min-Jung
MJ
Lee
Jae-Young
JY
Kim
Syng-Ill
SI
Lee
Hodaka
H
Sasaki
Declan P
DP
Lunny
E Birgitte
EB
Lane
Han-Sung
HS
Jung
D000818:Animals; D000943:Antigens, Differentiation / Q000096:biosynthesis; D002454:Cell Differentiation; D049109:Cell Proliferation; D018031:Connexin 43 / Q000096:biosynthesis; D004622:Embryo, Mammalian / Q000166:cytology; D005260:Female; D053823:Hedgehog Proteins / Q000096:biosynthesis*; D007150:Immunohistochemistry; D007633:Keratins / Q000096:biosynthesis*; D051379:Mice; D008813:Mice, Inbred ICR; D009024:Morphogenesis; D000072079:Patched Receptors; D000072081:Patched-1 Receptor; D018809:Proliferating Cell Nuclear Antigen / Q000096:biosynthesis; D011956:Receptors, Cell Surface / Q000096:biosynthesis*; D012470:Salivary Glands, Minor / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D015398:Signal Transduction; D013650:Taste Buds / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D014059:Tongue / Q000166:cytology / Q000196:embryology / Q000378:metabolism*
D000943:Antigens, Differentiation; D018031:Connexin 43; D053823:Hedgehog Proteins; D000072079:Patched Receptors; D000072081:Patched-1 Receptor; D018809:Proliferating Cell Nuclear Antigen; C000606240:Ptch1 protein, mouse; D011956:Receptors, Cell Surface; D007633:Keratins