Alt Burkhard, Reibe Saskia, Feitosa Natalia M, Elsalini Osama A, Wendl Thomas, Rohr Klaus B
Institute for Developmental Biology, University of Cologne, Gyrhofstrasse 17, 50923 Köln, Germany.
Dev Dyn. 2006 Jul;235(7):1872-83. doi: 10.1002/dvdy.20831.
The zebrafish thyroid gland shows a unique pattern of growth as a differentiated endocrine gland. Here, we analyze the onset of differentiation, the contribution of lineages, and the mode of growth of this gland. The expression of genes involved in hormone production and the establishment of epithelial polarity show that differentiation into a first thyroid follicle takes place early during embryonic development. Thyroid follicular tissue then grows along the pharyngeal midline, initially independently of thyroid stimulating hormone. Lineage analysis reveals that thyroid follicle cells are exclusively recruited from the pharyngeal endoderm. The ultimobranchial bodies that merge with the thyroid in mammals form separate glands in zebrafish as visualized by calcitonin precursor gene expression. Mosaic analysis suggests that the first thyroid follicle differentiating at 55 hours postfertilization corresponds later to the most anterior follicle and that new follicles are added caudally.
斑马鱼的甲状腺作为一个分化的内分泌腺，呈现出独特的生长模式。在此，我们分析了该腺体的分化起始、谱系贡献及生长方式。参与激素产生和上皮极性建立的基因表达表明，在胚胎发育早期就发生了向第一个甲状腺滤泡的分化。甲状腺滤泡组织随后沿咽中线生长，最初独立于促甲状腺激素。谱系分析显示，甲状腺滤泡细胞仅从咽内胚层募集。在哺乳动物中与甲状腺融合的后鳃体，在斑马鱼中形成独立的腺体，这可通过降钙素前体基因表达观察到。镶嵌分析表明，受精后55小时分化的第一个甲状腺滤泡，随后对应于最前端的滤泡，新的滤泡在尾端添加。
