Monell Chemical Senses Center, Philadelphia, Pennsylvania, United States of America.
Department of Life Science and Technology, Graduate School of Life Science and Technology, Tokyo Institute of Technology, Yokohama, Kanagawa, Japan.
PLoS One. 2022 Sep 2;17(9):e0267683. doi: 10.1371/journal.pone.0267683. eCollection 2022.
Continuous turnover of taste bud cells in the oral cavity underlies the homeostasis of taste tissues. Previous studies have demonstrated that Sox2+ stem cells give rise to all types of epithelial cells including taste bud cells and non-gustatory epithelial cells in the oral epithelium, and Sox2 is required for generating taste bud cells. Here, we show the dynamism of single stem cells through multicolor lineage tracing analyses in Sox2-CreERT2; Rosa26-Confetti mice. In the non-gustatory epithelium, unicolored areas populated by a cluster of cells expressing the same fluorescent protein grew over time, while epithelial cells were randomly labeled with multiple fluorescent proteins by short-term tracing. Similar phenomena were observed in gustatory epithelia. These results suggest that the Sox2+ stem cell population is maintained by balancing the increase of certain stem cells with the reduction of the others. In the gustatory epithelia, many single taste buds contained cells labeled with different fluorescent proteins, indicating that a single taste bud is composed of cells derived from multiple Sox2+ stem cells. Our results reveal the characteristics of Sox2+ stem cells underlying the turnover of taste bud cells and the homeostasis of taste tissues.
口腔中味蕾细胞的持续更新是味觉组织维持内稳态的基础。先前的研究表明，Sox2+干细胞产生包括味蕾细胞和口腔上皮中非味觉上皮细胞在内的所有上皮细胞类型，并且 Sox2 对于产生味蕾细胞是必需的。在这里，我们通过 Sox2-CreERT2；Rosa26-Confetti 小鼠中的多色谱系追踪分析显示了单个干细胞的动态性。在非味觉上皮中，随着时间的推移，表达相同荧光蛋白的一簇细胞组成的单彩色区域不断增大，而通过短期追踪，上皮细胞则随机被多个荧光蛋白标记。在味觉上皮中也观察到了类似的现象。这些结果表明，Sox2+干细胞群体通过平衡某些干细胞的增加和其他干细胞的减少来维持。在味觉上皮中，许多单个味蕾包含用不同荧光蛋白标记的细胞，这表明单个味蕾由来自多个 Sox2+干细胞的细胞组成。我们的结果揭示了 Sox2+干细胞在味蕾细胞更新和味觉组织维持内稳态中的特征。
