Phosphorylation of iodopsin, chicken red-sensitive cone visual pigment.
Phosphorylation of iodopsin, chicken red-sensitive cone visual pigment.
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碘紫红素、鸡红色敏感视锥视觉色素的磷酸化。
DOI：
10.1021/bi00495a013
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发表时间：
1990
期刊：
影响因子：
2.9
通讯作者：
Palczewski,K
中科院分区：
文献类型：
--
作者：
Fukada,Y;Kokame,K;Okano,T;Shichida,Y;Yoshizawa,T;McDowell,JH;Hargrave,PA;Palczewski,K
俄勒冈州波特兰97209。1990年5月22日收到；1990年7月30日收到修订稿件摘要：测定了鸡红敏锥体色素碘蛋白的羧基末端41个氨基酸的氨基酸序列。该序列与其他视觉色素的序列不同，但在结构上是同源的。它包含一个富含羟基氨基酸丝氨酸和苏氨酸的区域。在视紫红质相关的视杆细胞色素中，此类丝氨酸和苏氨酸已被确定为视紫红质激酶的磷酸化部位。光解视紫红质的磷酸化终止了其作为G蛋白激活剂在视觉转导中的功能。我们已经纯化和重组了鸡视紫质和鸡碘紫质，并证明它们被牛视紫质激酶磷酸化。鸡碘紫质的Km和Umax与牛视紫质相似，但有明显不同。结合其他数据，这些结果表明，视锥细胞中的视觉色素在吸收光线后，经历了与视杆细胞中的视觉色素相似的功能过程。
Portland, Oregon 97209. Received May 22, 1990; Revised Manuscript Received July 30, 1990 abstract: The amino acid sequence has been determined for the carboxyl-terminal 41 amino acids of chicken red-sensitive cone pigment, iodopsin. This sequence is distinct from but structurally homologous to that of other visual pigments. It contains a region rich in the hydroxy amino acids serine and threonine. In the related rod cell visual pigment, rhodopsin, such serines and threonines have previously been identified as sites for phosphorylation by rhodopsin kinase. Phosphorylation of photolyzed rhodopsin serves to terminate its ability to function in visual transduction as an activator of G-protein. We have purified and reconstituted both chicken rhodopsin and chicken iodopsin and shown them to be phosphorylated by bovine rhodopsin kinase. Chicken iodopsin has a Km and Umax similar to butdistinguishably different from that for bovine rhodopsin. These results, in conjunctionwith other data, suggest that visual pigments in cone cells, upon absorption of light, undergo functional processes similar to those of the visual pigments in rod cells.