BINDING-SITES OF PHOTORECEPTOR-SPECIFIC ANTIBODIES COS-1, OS-2 AND AO
BINDING-SITES OF PHOTORECEPTOR-SPECIFIC ANTIBODIES COS-1, OS-2 AND AO
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DOI：
10.3109/02713689309020400
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发表时间：
1993-10-01
影响因子：
2
通讯作者：
SZEL, A
中科院分区：
文献类型：
--
作者：
ROHLICH, P;SZEL, A
利用鸡红敏视锥色素（碘视素）和合成的视锥色素和视杆色素多肽，用免疫细胞化学方法找到了光受体特异性抗体的结合位点。碘紫素阻断单克隆抗体COS-1和OS-2免疫标记的能力直接证明了这两种抗体对视觉色素是特异性的。用免疫细胞化学方法对含和不含洗涤剂的视网膜进行观察，并用电镜对视锥光感受器膜进行标记，发现COS-1和OS-2的结合位点位于膜的细胞质侧。通过对主要来自视锥色素c端区域的合成肽的测试，我们发现人类红/绿-和鸡红敏感视锥色素的后6个氨基酸组成的结构域完全阻断了COS-1的免疫标记，而人类蓝视锥色素的后12个氨基酸组成的序列则有效阻断了OS-2的结合。因此，这两种单克隆抗体都可视为c端特异性抗体。发现OS-2与适应黑暗的光色素的结合比适应光色素的结合更强。牛视紫红质n端合成肽几乎完全抑制了多克隆视紫红质抗体AO的结合，表明该抗体在组织环境中主要结合于视紫红质n端结构域。
The chicken red-sensitive cone visual pigment (iodopsin) and several synthetic peptides of cone and rod visual pigments were used to find the binding sites of our photoreceptor-specific antibodies with immunocytochemistry. The ability of iodopsin to block immunolabeling with monoclonal antibodies COS-1 and OS-2 furnished direct evidence that both antibodies are specific to visual pigments. Immunocytochemistry on whole-mount retinas with and without detergent, as well as electron microscopic labeling of cone photoreceptor membranes revealed the binding sites of COS-1 and OS-2 to be on the cytoplasmic side of the membrane. By testing several synthetic peptides, mainly from the C-terminal region of the cone visual pigments, we found that the domain consisting of the last 6 amino acids of the human red/green-, and the chicken red-sensitive cone pigments completely blocked immunolabeling with COS-1, while the sequence consisting of the last 12 amino acids of the human blue cone pigment was effective to block the binding of OS-2. Both monoclonals can be regarded therefore C-terminal specific antibodies. OS-2 was found to bind to the dark-adapted photopigment more strongly than to the light-adapted one. The binding of the polyclonal rhodopsin antibody AO was almost entirely inhibited by the N-terminal synthetic peptide of bovine rhodopsin indicating that this antibody binds primarily to the N-terminal domain of rhodopsin in a tissue environment.