Kimura Y, Matsunami H, Inoue T, Shimamura K, Uchida N, Ueno T, Miyazaki T, Takeichi M
Department of Biophysics, Faculty of Science, Kyoto University, Japan.
Dev Biol. 1995 May;169(1):347-58. doi: 10.1006/dbio.1995.1149.
Cadherin-11 (cad-11) is a novel member of the cadherin family of cell adhesion molecules, having recently been identified by means of the polymerase chain reaction. To study the function and expression of this molecule, we cloned mouse, cad-11 cDNA. Transfection of L cells with cDNA led them to acquire a typical cadherin-dependent cell-cell adhesiveness, and the L cells expressing cad-11 did not coaggregate with L cells expressing E-, P-, N-, or R-cadherin when they were mixed, indicating that this novel cadherin has a homophilic binding specificity, as found for other cadherins. To determine the developmental expression pattern of this molecule, we performed in situ hybridization analysis on early mouse embryos. Cad-11 first appeared in mesodermal layers only in the head and tail regions at the mid-to-late primitive streak stages. In the head, this appearance was followed by strong expression in mesenchymal tissues including branchial arches. In the trunk, the paraxial mesoderm initially did not express cad-11. However, as the somites formed, they expressed cad-11, and this expression was strictly correlated with their initial condensation and segregation from the presomitic mesoderm. The cad-11 expression in the somites was eventually restricted to sclerotome cells. As the limb buds developed, cad-11 appeared in the distal portion of the limb mesenchyme, and, at later stages, its expression was most evident at the peripheral mesenchyme. Cad-11 was thus expressed by restricted populations of mesenchymal cells in early embryos, although it was also expressed in parts of the neural tube, such as the optic vesicle and dorsal midline, and in part of the otic vesicle. As a step to investigate the role of cad-11 in mesenchymal cell adhesion, we dissociated the limb bud mesenchyme into single cells, pelleted them, and cultured them as aggregates. In these cultures, cad-11-positive cells clearly sorted out of the negative cell population, suggesting that cad-11 might be involved in selective association of mesenchymal cells. For comparison, we studied the expression of N-cadherin and found that the expressions of these two cadherins were differential, and complementary in some tissues. These results suggest that cad-11 is involved in specific associations of subsets of mesenchymal cells and also of some neural cells during early embryogenesis.
钙黏蛋白-11（cad-11）是细胞黏附分子钙黏蛋白家族的一个新成员，最近通过聚合酶链反应得以鉴定。为了研究该分子的功能和表达，我们克隆了小鼠cad-11 cDNA。用cDNA转染L细胞使其获得了典型的钙黏蛋白依赖性细胞间黏附性，并且当表达cad-11的L细胞与表达E-、P-、N-或R-钙黏蛋白的L细胞混合时，它们不会共聚集，这表明这种新的钙黏蛋白具有同嗜性结合特异性，这与其他钙黏蛋白的情况相同。为了确定该分子的发育表达模式，我们对早期小鼠胚胎进行了原位杂交分析。Cad-11最早在原条期中期至晚期仅在头部和尾部区域的中胚层中出现。在头部，这种出现之后是在包括鳃弓在内的间充质组织中的强表达。在躯干中，轴旁中胚层最初不表达cad-11。然而，随着体节的形成，它们开始表达cad-11，并且这种表达与它们从体节前期中胚层的初始凝聚和分离密切相关。体节中cad-11的表达最终局限于硬骨细胞。随着肢芽的发育，cad-11出现在肢芽间充质的远端部分，并且在后期，其表达在周边间充质中最为明显。因此，cad-11在早期胚胎中由特定群体的间充质细胞表达，尽管它也在神经管的部分区域表达，如视泡和背中线，以及部分耳泡中表达。作为研究cad-11在间充质细胞黏附中作用的一个步骤，我们将肢芽间充质解离成单个细胞，将它们制成小丸，并作为聚集体进行培养。在这些培养物中，cad-11阳性细胞明显从阴性细胞群体中分离出来，这表明cad-11可能参与间充质细胞的选择性结合。为了进行比较，我们研究了N-钙黏蛋白的表达，发现这两种钙黏蛋白的表达存在差异，并且在某些组织中具有互补性。这些结果表明，cad-11在早期胚胎发育过程中参与间充质细胞亚群以及一些神经细胞的特异性结合。
