Shoji H, Ito T, Wakamatsu Y, Hayasaka N, Ohsaki K, Oyanagi M, Kominami R, Kondoh H, Takahashi N
Institute for Molecular and Cellular Biology, Osaka University, Japan.
Mech Dev. 1996 May;56(1-2):25-39. doi: 10.1016/0925-4773(96)00509-6.
Here we report the identification of a novel homeobox gene family Dbx in mouse, which consists of Dbx and Dbx2. The two genes share similar structural organization and are encoded by different chromosomes. The predicted Dbx and Dbx2 proteins share 85% identity in their homeodomain amino acid sequences, but otherwise showed no significant similarity. Characterization of the expression of these two genes in the embryos suggested their role in the development of the CNS. In the forebrain, Dbx is expressed in various regions, while Dbx2 showed a more restricted pattern of expression. In the midbrain, the expression domains of Dbx and Dbx2 overlap along the dorso-lateral wall of the ventricle. In the hindbrain and spinal cord, both genes are expressed in the boundary separating the basal and alar plates, which seems to correspond to the sulcus limitans. Expression of the Dbx/Dbx2 genes is restricted to the ventricular region of the embryonic CNS except for that of Dbx in the septum of the telencephalon. Together these observations indicate possible participation of the members of the Dbx family in regionalization of the CNS. While the expression of Dbx was restricted to the CNS, Dbx2 was also expressed in some of the mesenchymal cells, such as limb buds and tooth germs.
在此，我们报告在小鼠中鉴定出一个新的同源框基因家族Dbx，它由Dbx和Dbx2组成。这两个基因具有相似的结构组织，且由不同的染色体编码。预测的Dbx和Dbx2蛋白在其同源结构域氨基酸序列中具有85%的同一性，但在其他方面没有显著相似性。对这两个基因在胚胎中的表达特征分析表明它们在中枢神经系统发育中发挥作用。在前脑，Dbx在各个区域表达，而Dbx2的表达模式更为局限。在中脑，Dbx和Dbx2的表达域沿着脑室的背侧壁重叠。在后脑和脊髓中，这两个基因都在分隔基板和翼板的边界处表达，这似乎对应于界沟。Dbx/Dbx2基因的表达局限于胚胎中枢神经系统的脑室区域，但端脑隔中的Dbx除外。这些观察结果共同表明Dbx家族成员可能参与中枢神经系统的区域化。虽然Dbx的表达局限于中枢神经系统，但Dbx2也在一些间充质细胞中表达，如肢芽和牙胚。
