Ohkubo S, Yamada E, Endo T, Itoh H, Hidaka H
Biochem Biophys Res Commun. 1984 Jan 30;118(2):460-6. doi: 10.1016/0006-291x(84)91325-1.
Ca2+-activated, phospholipid-dependent protein kinase from rabbit retina was partially purified. Vitamin A acid (retinoic acid) stimulated this protein kinase in the presence of Ca2+, while other metabolites of vitamin A such as retinol or retinal were less effective. The order of the extent of phosphorylation of the various substrate proteins by this protein kinase was identical in the presence of vitamin A acid or phosphatidylserine. The major spots of the 32P labeled peptide from histone H1 phosphorylated in the presence of vitamin A acid by this protein kinase did not differ from those obtained from histone H1 phosphorylated in the presence of phosphatidylserine. Retinol caused a further enhancement of the enzymatic activity, whereas the addition of retinal inhibited the activation by vitamin A acid. Thus, vitamin A and its metabolites may play an important role in the regulation of Ca2+-activated, phospholipid-dependent protein kinase activity in the retina.
兔视网膜中钙激活的磷脂依赖性蛋白激酶被部分纯化。视黄酸（维甲酸）在钙离子存在的情况下刺激这种蛋白激酶，而维生素A的其他代谢产物如视黄醇或视黄醛则效果较差。在视黄酸或磷脂酰丝氨酸存在的情况下，该蛋白激酶对各种底物蛋白的磷酸化程度顺序相同。在视黄酸存在下由该蛋白激酶磷酸化的组蛋白H1的32P标记肽的主要斑点与在磷脂酰丝氨酸存在下从组蛋白H1获得的斑点没有差异。视黄醇导致酶活性进一步增强，而视黄醛的添加则抑制视黄酸的激活作用。因此，维生素A及其代谢产物可能在视网膜中钙激活的磷脂依赖性蛋白激酶活性的调节中起重要作用。
