Kimura S, Ward J M, Minoo P
Laboratory of Metabolism, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Biochimie. 1999 Apr;81(4):321-7. doi: 10.1016/s0300-9084(99)80077-7.
Targeted disruption of the homeobox gene T/ebp (Ttf1) in mice results in ablation of the thyroid and pituitary, and severe deformities in development of the lung and hypothalamus. T/ebp is expressed in the thyroid, lung, and ventral forebrain during normal embryogenesis. Examination of thyroid development in T/ebp homozygous null mutant embryos revealed that the thyroid rudiment is initially formed but is eliminated through apoptosis. Absence of T/EBP expression in the lung primordium does not activate apoptosis since a lung tissue, albeit dysmorphic, is nevertheless formed in T/ebp-/- embryos. These results demonstrate that T/EBP is not required for the initial specification of thyroid or lung primordia, but is absolutely essential for the development and morphogenesis of these organs.
在小鼠中对同源框基因T/ebp（Ttf1）进行靶向破坏会导致甲状腺和垂体缺失，以及肺和下丘脑发育严重畸形。在正常胚胎发育过程中，T/ebp在甲状腺、肺和腹侧前脑表达。对T/ebp纯合无效突变胚胎的甲状腺发育进行检查发现，甲状腺原基最初形成，但通过凋亡被消除。肺原基中缺乏T/EBP表达不会激活凋亡，因为在T/ebp - / -胚胎中仍会形成尽管形态异常但仍为肺组织。这些结果表明，T/EBP对于甲状腺或肺原基的初始特化不是必需的，但对于这些器官的发育和形态发生绝对至关重要。
