Phosphatidylinositol-stimulated phosphorylation of an inhibitory subunit of cGMP phosphodiesterase in vertebrate rod photoreceptors.
Phosphatidylinositol-stimulated phosphorylation of an inhibitory subunit of cGMP phosphodiesterase in vertebrate rod photoreceptors.
复制标题
脊椎动物视杆光感受器中磷脂酰肌醇刺激 cGMP 磷酸二酯酶抑制亚基的磷酸化。
DOI：
10.1073/pnas.88.10.4333
复制
发表时间：
1991
影响因子：
11.1
通讯作者：
Yamazaki,A
中科院分区：
文献类型：
--
作者：
Hayashi,F;Lin,GY;Matsumoto,H;Yamazaki,A
来自脊椎动物视杆光感受器（青蛙、蟾蜍和牛）的cGMP磷酸二酯酶的抑制性亚基（P γ）被来自完整青蛙视杆外节的胞质蛋白激酶磷酸化。蛙P γ的磷酸化被磷脂酰肌醇刺激，而不是由cAMP或cGMP。一维和二维凝胶电泳显示，70-80%的P γ磷酸化与1摩尔磷酸盐每青蛙P γ在最佳条件下。一个肽，来自牛P γ的活性结构域也被磷酸化。通过向反应混合物中加入肽来抑制青蛙P γ的磷酸化。蛙P γ的磷酸化也被抑制，通过添加transducin亚基或活性（P γ-少）cGMP磷酸二酯酶。另一方面，冈田酸增强P γ磷酸化，表明胞质组分中存在蛋白磷酸酶。这些数据表明，在脊椎动物视杆细胞的cGMP磷酸二酯酶的调节的另一种机制。
An inhibitory subunit (P gamma) of cGMP phosphodiesterase from vertebrate rod photoreceptors (frog, toad, and bovine) was phosphorylated by cytosolic protein kinase(s) derived from intact frog rod outer segments. The phosphorylation of frog P gamma was stimulated by phosphatidylinositol but not by cAMP or cGMP. One- and two-dimensional gel electrophoresis revealed that 70-80% of P gamma was phosphorylated with 1 mol of phosphate per frog P gamma under optimal conditions. A peptide that derived from an active domain of bovine P gamma was also phosphorylated. Phosphorylation of frog P gamma was inhibited by addition of the peptide to the reaction mixture. Phosphorylation of frog P gamma was also inhibited by addition of transducin subunits or active (P gamma-less) cGMP phosphodiesterase. Okadaic acid, on the other hand, enhanced P gamma phosphorylation, suggesting the presence of protein phosphatase(s) in the cytosolic fraction. These data suggest another mechanism for the regulation of cGMP phosphodiesterase in vertebrate rod photoreceptors.