Tsukamoto Y, Matsumoto T, Taira E, Kotani T, Yamate J, Takaha N, Tatesaki R, Namikawa T, Miki N, Sakuma S
Department of Veterinary Pathology, College of Agriculture, Osaka Prefecture University, 1-1 Gakuencho, Sakai, Osaka 593, Japan.
Cell Tissue Res. 1998 Apr;292(1):137-42. doi: 10.1007/s004410051043.
Gicerin, a cell-adhesion molecule belonging to the immunoglobulin superfamily, has both homophilic and heterophilic binding activities to neurite outgrowth factor, an extracellular matrix molecule in the laminin family. Gicerin is thought to play a role in the normal development of chicken kidney, because it is expressed abundantly in the embryonic organ and only slightly in the mature organ. In this study, we have examined the adhesive activity of gicerin in the kidney to characterize its function in organogenesis. We have also examined the function of gicerin in chicken nephroblastomas ("embryonic nephromas"), which show various structures resembling those in embryonic kidneys. Immunohistochemically, the expression patterns of gicerin and neurite outgrowth factor in nephroblastomas are similar to those of embryonic kidneys. Cell-aggregation assays have shown that primary culture cells from both embryonic kidneys and nephroblastomas have strong aggregation activities, and that each aggregation is partially inhibited by gicerin antibody. In contrast, cells from adult kidney exhibit weak aggregation activity that is not inhibited by the antibody. In addition, ligand blot analysis has revealed that gicerins in embryonic kidney and nephroblastoma bind to purified neurite outgrowth factor, whereas extracts from adult kidney show no positive reaction. These findings suggest that the homophilic and heterophilic adhesive activities of gicerin are involved in the formation of both normal kidney and nephroblastoma.
吉塞林是一种属于免疫球蛋白超家族的细胞粘附分子，对神经突生长因子具有同嗜性和异嗜性结合活性，神经突生长因子是层粘连蛋白家族中的一种细胞外基质分子。吉塞林被认为在鸡肾的正常发育中发挥作用，因为它在胚胎器官中大量表达，而在成熟器官中仅少量表达。在本研究中，我们检测了吉塞林在肾脏中的粘附活性，以表征其在器官发生中的功能。我们还检测了吉塞林在鸡肾母细胞瘤（“胚胎性肾瘤”）中的功能，肾母细胞瘤显示出各种类似于胚胎肾脏的结构。免疫组织化学分析表明，肾母细胞瘤中吉塞林和神经突生长因子的表达模式与胚胎肾脏相似。细胞聚集试验表明，来自胚胎肾脏和肾母细胞瘤的原代培养细胞都具有很强的聚集活性，并且每种聚集都被吉塞林抗体部分抑制。相比之下，来自成年肾脏的细胞表现出较弱的聚集活性，且不受该抗体抑制。此外，配体印迹分析表明，胚胎肾脏和肾母细胞瘤中的吉塞林与纯化的神经突生长因子结合，而成年肾脏提取物未显示阳性反应。这些发现表明，吉塞林的同嗜性和异嗜性粘附活性参与了正常肾脏和肾母细胞瘤的形成。
