Hayashi F, Yamazaki A
Cellular and Molecular Biology Group, Los Alamos National Laboratory, University of California, NM 87545.
Proc Natl Acad Sci U S A. 1991 Jun 1;88(11):4746-50. doi: 10.1073/pnas.88.11.4746.
Guanylate cyclase from rod photoreceptors of amphibian (toad, Bufo marinus, and frog, Rana catesbeiana) and bovine retinas was solubilized and purified by a single chromatography step on a GTP-agarose column. Silver staining of purified amphibian enzymes in SDS/polyacrylamide gels disclosed a doublet band (110 and 115 kDa), while the bovine enzyme appeared as a singlet band (110 kDa). The identification of these guanylate cyclases was confirmed using three chromatography systems with the purified enzymes. Specific binding to Con A-Sepharose suggested that rod guanylate cyclase is a glycoprotein. Two-dimensional gel electrophoresis of purified toad, frog, and bovine enzymes resolved two, three, and five variants, respectively, that differed in isoelectric point. Two variants of toad guanylate cyclase showed differences in various characterizations. These data suggest multiple mechanisms for regulation of guanylate cyclase activity in vertebrate rod photoreceptors.
通过在GTP-琼脂糖柱上进行单一色谱步骤，溶解并纯化了来自两栖动物（蟾蜍，海蟾蜍，和青蛙，牛蛙）和牛视网膜的视杆光感受器中的鸟苷酸环化酶。在SDS/聚丙烯酰胺凝胶中对纯化的两栖动物酶进行银染，显示出一条双峰带（110和115 kDa），而牛酶则呈现为单条带（110 kDa）。使用三种色谱系统对纯化的酶进行分析，证实了这些鸟苷酸环化酶的鉴定。与伴刀豆球蛋白A-琼脂糖的特异性结合表明视杆鸟苷酸环化酶是一种糖蛋白。对纯化的蟾蜍、青蛙和牛酶进行二维凝胶电泳，分别解析出两种、三种和五种等电点不同的变体。蟾蜍鸟苷酸环化酶的两种变体在各种特性上表现出差异。这些数据表明脊椎动物视杆光感受器中鸟苷酸环化酶活性的调节存在多种机制。
