Thirumangalathu Shoba, Barlow Linda A
Department of Cell and Developmental Biology and the Rocky Mountain Taste & Smell Center, University of Colorado Denver School of Medicine, Aurora, Colorado 80045, USA.
Ann N Y Acad Sci. 2009 Jul;1170:34-8. doi: 10.1111/j.1749-6632.2009.04371.x.
In mammals, the homogeneous lingual epithelium in the process of development forms specialized placodal cells that undergo a series of morphogenetic changes to form a papilla. Taste buds appear in the papillary epithelium around birth and thus papillae serve to house the taste buds in the adult. However, evidence for a precise lineage relationship between a putative embryonic taste progenitor population and functional adult taste buds has so far been elusive and is primarily indirect. Also, mammalian taste papillae are reminiscent of epithelial appendages suggesting that the mesenchymal tissue of the papillae could be involved in the formation of these lingual structures. These major questions in the field of mammalian taste development have remained unanswered due to lack of fate mapping studies that would label embryonic cell populations and remain indelibly marked in the adult. Taking advantage of a genetic fate mapping approach to label cell populations both in the lingual epithelium and mesenchyme and following their fate during development would be an ideal way to assess each of these tissues contribution in taste bud formation. Fate mapping studies using tissue specific cre strains crossed with reporter alleles would uncover unique features in the formation of these specialized sensory cells and also provide us with an in vivo model system for taste organ specific experimental manipulations during development.
在哺乳动物中，发育过程中均匀的舌上皮形成特化的基板细胞，这些细胞经历一系列形态发生变化以形成乳头。味蕾在出生前后出现在乳头上皮中，因此乳头在成体中用于容纳味蕾。然而，迄今为止，关于假定的胚胎味觉祖细胞群与功能性成体味蕾之间精确的谱系关系的证据一直难以捉摸，且主要是间接的。此外，哺乳动物的味觉乳头让人联想到上皮附属器，这表明乳头的间充质组织可能参与了这些舌结构的形成。由于缺乏能够标记胚胎细胞群并在成体中留下不可磨灭标记的命运图谱研究，哺乳动物味觉发育领域的这些主要问题一直未得到解答。利用遗传命运图谱方法标记舌上皮和间充质中的细胞群，并追踪它们在发育过程中的命运，将是评估这些组织在味蕾形成中各自贡献的理想方式。使用与报告基因等位基因杂交的组织特异性cre菌株进行命运图谱研究，将揭示这些特化感觉细胞形成过程中的独特特征，也为我们提供一个在发育过程中对味觉器官进行特定实验操作的体内模型系统。
