Orlov N Ia, Tishchenkov V G, Bagirov I G, Shnyrov V L
Biofizika. 1983 Sep-Oct;28(5):793-9.
It is shown that nearly 70% water--soluble protein of the frog retina outer segments (ROS) consist of three polypeptides with molecular weights 39 000, 36 000 and less than 15 000 daltons. These proteins are present in equal proportions and are, apparently, the subunits of a tightly bound protein complex. The subunit of 39 000 daltons is responsible for guanyl nucleotides binding. Parameters of the investigated GTP-binding complex are similar to transducyn which transmits excitation from bleached rhodopsin to PDE molecules in the bovine retina ROS. The thermodynamic state of GTP-binding protein in frog retina ROS depends on the functional state of the photoreceptor membrane, as shown by microcalorimetric method.
结果表明，青蛙视网膜外段（ROS）中近70%的水溶性蛋白质由分子量分别为39000、36000和小于15000道尔顿的三种多肽组成。这些蛋白质以相等的比例存在，显然是紧密结合的蛋白质复合物的亚基。39000道尔顿的亚基负责鸟苷核苷酸的结合。所研究的GTP结合复合物的参数与转导素相似，转导素将漂白视紫红质的激发传递给牛视网膜ROS中的PDE分子。微量量热法表明，青蛙视网膜ROS中GTP结合蛋白的热力学状态取决于光感受器膜的功能状态。
