Notch‐associated gene expression in embryonic and adult taste papillae and taste buds suggests a role in taste cell lineage decisions
Notch‐associated gene expression in embryonic and adult taste papillae and taste buds suggests a role in taste cell lineage decisions
复制标题
DOI：
10.1002/cne.10787
复制
发表时间：
2003-09
影响因子：
2.5
通讯作者：
Y. Seta;C. Seta;L. Barlow
中科院分区：
文献类型：
--
作者：
Y. Seta;C. Seta;L. Barlow
Notch信号通路参与细胞发育过程中的命运决定。为了探索这一信号级联在味觉系统中的作用，我们利用原位杂交技术研究了Notch信号基因在胎儿和成年小鼠舌头中的表达模式。四种小鼠Notch受体中的三种及其配体Delta - like 1 （Dll - 1）、Jagged1和Jagged2以及三种转录因子Hes1、Hes6和Mash1在胚胎味觉上皮中表达。在胚胎期E14.5， Notch1、Jagged1和Jagged2在乳头和一般舌上皮中广泛表达，首次在环瓣乳头中检测到表达。相比之下，Mash1和Hes6仅局限于发育中的乳头顶端区域的少数上皮细胞。到E18.5，许多基因现在在乳头上皮中表现出双峰表达模式：它们在稀疏的细胞簇中在顶部和背部表达，而更多的腹侧表达通常发生在整个沟的较低区域。比较乳头神经支配程度与Mash1、Hes6的表达情况。在E14.5时，Hes6和Mash1已经在少量上皮细胞中表达，PGP9.5免疫反应纤维尚未侵入上皮，与神经接触前味蕾原基的规范一致。所有被检测的基因（除了Notch2）也在成年小鼠的环形味蕾内的细胞亚群中表达，尽管Notch1仅限于味蕾附近的基底细胞。胚胎Notch相关基因表达在环形乳头形态分化后的开始表明，这种信号级联可能指定了已经指定的味觉乳头内的味觉受体细胞系。同样，Notch基因在成人味蕾中的表达表明在细胞谱系决定和细胞更新中继续发挥作用。[j] .中华神经医学杂志，2004,34(4):559 - 561。©2003 Wiley‐Liss, Inc。
The Notch signaling pathway is involved in cell fate decisions during development. To explore the role of this signaling cascade in the taste system, we investigated the expression patterns of Notch signaling genes in fetal and adult mouse tongues using in situ hybridization. Three of the four murine Notch receptors, their ligands, Delta‐like 1 (Dll‐1), Jagged1, and Jagged2, as well as three transcription factors, Hes1, Hes6, and Mash1, are expressed in the embryonic taste epithelium. Expression is first detected in the circumvallate papilla at embryonic day E14.5, when Notch1, Jagged1, and Jagged2 are expressed broadly in the papilla and general lingual epithelium. In contrast, Mash1 and Hes6 are restricted to only a few epithelial cells in the apical region of the developing papilla. By E18.5, many of the genes now exhibit a bimodal expression pattern in the papillary epithelium: apically and dorsally they are expressed in sparse clusters of cells, while more ventrally expression typically occurs throughout the lower regions of the trenches. The extent of papilla innervation was compared with Mash1 and Hes6 expression. At E14.5, when Hes6 and Mash1 are already expressed in small numbers of epithelial cells, PGP9.5 immunoreactive fibers have not yet invaded the epithelium, consistent with the specification of taste bud primordia prior to nerve contact. All of the genes examined (except Notch2) are also expressed in subsets of cells within circumvallate taste buds in adult mice, although Notch1 is restricted to basal cells adjacent to taste buds. The onset of embryonic Notch associated gene expression after the morphological differentiation of the circumvallate papilla argues that this signaling cascade may specify taste receptor cell lineages within an already specified taste papilla. Similarly, Notch gene expression in adult taste buds suggests continued roles in cell lineage determination and cell turnover. J. Comp. Neurol. 464:49–61, 2003. © 2003 Wiley‐Liss, Inc.