Takeuchi J K, Koshiba-Takeuchi K, Matsumoto K, Vogel-Höpker A, Naitoh-Matsuo M, Ogura K, Takahashi N, Yasuda K, Ogura T
Nara Institute of Science and Technology Graduate School of Biological Sciences, Ikoma, Japan.
Nature. 1999 Apr 29;398(6730):810-4. doi: 10.1038/19762.
Much progress has been made in understanding limb development. Most genes are expressed equally and in the same pattern in the fore- and hindlimbs, which nevertheless develop into distinct structures. The T-box genes Tbx5 and Tbx4, on the other hand, are expressed differently in chick wing (Tbx5) and leg (Tbx4) buds. Molecular analysis of the optomotor blind gene, which belongs to the same family of transcription factors, has revealed that this gene is involved in the transdetermination of Drosophila wing and leg imaginal discs. In addition, expression of Tbx5 and Tbx4 correlates well with the identity of ectopic limb buds induced by fibroblast growth factor. Thus, it is thought that Tbx5 and Tbx4 might be involved in determining limb identity. Another candidate is the Pitx1 gene, which encodes a bicoid-type homeodomain transcription factor that is expressed in leg buds. Here we determine the importance of these factors in establishing limb identity.
在理解肢体发育方面已经取得了很大进展。大多数基因在前肢和后肢中以相同的模式平等表达，但它们却发育成不同的结构。另一方面，T-box基因Tbx5和Tbx4在鸡胚翅芽（Tbx5）和腿芽（Tbx4）中的表达不同。对属于同一转录因子家族的视动盲基因进行分子分析发现，该基因参与果蝇翅和腿成虫盘的转决定。此外，Tbx5和Tbx4的表达与成纤维细胞生长因子诱导的异位肢体芽的特征密切相关。因此，人们认为Tbx5和Tbx4可能参与确定肢体特征。另一个候选基因是Pitx1基因，它编码一种在腿芽中表达的类双尾型同源结构域转录因子。在这里，我们确定了这些因子在建立肢体特征中的重要性。
