Broekhuyse R M, Kuhlmann E D, Leunissen L J, van de Scheur H M, Verkleij A J
Doc Ophthalmol. 1986 May 15;62(4):325-35. doi: 10.1007/BF00168264.
The localization of S-antigen in ultra-cryosections of rat retina has been studied and compared with that of opsin by immunoelectron microscopy. Monospecific antisera to both proteins, and Protein A-coated gold particles of two sizes were used for (double) labeling. In the light-adapted retina, S-antigen showed codistribution with opsin in the rod outer segments. S-antigen labeling was diminished in dark-adapted retina. In retina pigment epithelium, multi-layered bodies were found containing S-antigen and rhodopsin representing spent rod outer segment fragments. In addition to theoretical considerations, there is indication that S-antigen is closely associated with the cytoplasmic surface of rod outer segment disc membranes. It seems moreover likely that S-antigen and opsin are closely associated in the illuminated retina. An important reason for this assumption was the observation that double labeling experiments showed interference of the antibodies to both antigens probably due to steric hinderance. The present results are complementary to, and in agreement with biochemical data from literature and point to an important function of S-antigen in the process of phototransduction.
通过免疫电子显微镜研究了S抗原在大鼠视网膜超低温切片中的定位，并与视蛋白的定位进行了比较。使用针对这两种蛋白质的单特异性抗血清以及两种大小的蛋白A包被金颗粒进行（双重）标记。在光适应的视网膜中，S抗原在视杆外段与视蛋白共分布。在暗适应的视网膜中，S抗原标记减少。在视网膜色素上皮中，发现多层小体含有S抗原和视紫红质，代表用过的视杆外段片段。除了理论上的考虑外，有迹象表明S抗原与视杆外段盘膜的细胞质表面密切相关。此外，在光照的视网膜中，S抗原和视蛋白似乎密切相关。这一假设的一个重要原因是观察到双重标记实验显示两种抗原的抗体相互干扰，可能是由于空间位阻。目前的结果与文献中的生化数据互补且一致，并指出S抗原在光转导过程中具有重要作用。
