甲状腺转录因子-2在C57BL/6J小鼠腭突发育过程中的时空变化

The spatial-temporal changes in expression of thyroid transcription factor-2 during development of C57BL/6J mouse palate

目的探讨C57BL／6J小鼠继发腭发育过程中，甲状腺转录因子（TTF）-2表达的时空变化规律，探讨TTF-2在腭突形成中的作用。方法于小鼠妊娠12、13、14、15d分别断颈处死各6只孕鼠，无菌条件取出胚胎，解离腭突。应用逆转录聚合酶链反应（RT-PCR）、Westernblot和免疫组织化学染色方法定量、定位检测TTF-2在腭突中的表达。结果免疫组织化学定位检查在C57BL／6J小鼠的腭突发育过程（E12-E14）中，在腭突中嵴上皮细胞均有TTF-2的表达，而在腭突问充质细胞未见TTF-2的表达；腭突融合时，已不能检测到TTF-2表达。TTF-2在腭突形成、上抬、接触的表达差异具有统计学意义（P〈0．05），以E13为最高，RT-PCR和Westernblot结果一致。结论TTF．2在腭突发育过程中的表达有时空性，推测TTF-2与腭突中嵴上皮细胞的分化抑制和转归相关。

Objective To explore the spatial-temporal regularity in expression of thyroid transcription factor-2（TTF-2） and to understand its role during development of C57BL/6J mouse palate. Methods The palatal shelves from the C57BL/6J mouse embryos were microdissected in aseptic condition on days 12, 13, and 14 of gestation. Each day, six pregnant mice were sacrificed. The reverse transcription-polymerase chain reaction（RT-PCR）, Western blot and immunohistochemistry methods were used to detect semi-quantitative and qualitative expression of TTF-2 in palatal shelves. Results In the process of the C57BL/6J mouse palatal shelves growth（embryonic 12 day, El2）, elevation（El3） and touch（El4）, TTF-2 was expressed in palatal medial edge epithelium（MEE）, but no TTF-2 was found in palatal mesenchymal cells by immunohistochemistry location. TTF-2 was not expressed in the MEE of shelf fusing（El5）. A significant difference was found, and the highest expression was obtained at E13（P〈0.05）. This finding was consistent with the RT-PCR and Western blot results on the expression of TTF-2 in the palatal shelves of E12, El3, and El4. Conclusion The expression of TTF-2 during development of C57BL/6J mouse palatal shelves showed spatial-temporal changes correlating with cell differentiation and transformation.