Miura Hirohito, Kusakabe Yuko, Kato Hiromi, Miura-Ohnuma Jun, Tagami Mizuho, Ninomiya Yuzo, Hino Akihiro
National Food Research Institute, 2-1-12 Kannondai, Ibaraki Tsukuba-shi 305-8642, Japan.
Gene Expr Patterns. 2003 Aug;3(4):427-30. doi: 10.1016/s1567-133x(03)00081-4.
In mammals, taste buds are maintained by continuous turnover of cells, even in adulthood. Cell proliferation and differentiation continue to produce taste cells, which express various genes related to taste reception. We found the co-expression of Sonic hedgehog (Shh) with Prox1 and that of Nkx2.2 with Mash1 in adult mouse taste buds. Whereas Prox1was expressed strongly in cells in the basal region of mouse taste buds where Shh was co-expressed, it was expressed weakly in almost all taste bud cells lacking Shh expression. At 0.5 day after birth, when taste cells have not yet differentiated, the expressions of Shh and Prox1 completely overlapped in the epithelium of circumvallate papillae. Nkx2.2 was observed in cells expressing Mash1, but not in cells expressing genes related to taste reception, such as gustducin and T1R3. Almost all fusiform cells expressing Mash1 co-expressed Nkx2.2, while the majority of round cells expressing Mash1 in the basal region of taste buds lacked Nkx2.2 expression.
在哺乳动物中，即使在成年期，味蕾也通过细胞的持续更新得以维持。细胞增殖和分化持续产生味觉细胞，这些细胞表达与味觉感受相关的各种基因。我们发现成年小鼠味蕾中，音猬因子（Shh）与Prox1共表达，以及Nkx2.2与Mash1共表达。虽然Prox1在与Shh共表达的小鼠味蕾基部区域的细胞中强烈表达，但在几乎所有缺乏Shh表达的味蕾细胞中表达较弱。出生后0.5天，当味觉细胞尚未分化时，Shh和Prox1的表达在轮廓乳头的上皮中完全重叠。在表达Mash1的细胞中观察到Nkx2.2，但在表达与味觉感受相关基因（如味觉传导素和T1R3）的细胞中未观察到。几乎所有表达Mash1的梭形细胞都共表达Nkx2.2，而在味蕾基部区域表达Mash1的大多数圆形细胞缺乏Nkx2.2表达。
