Tanaka K, Tolbert N E
Plant Physiol. 1966 Feb;41(2):313-8. doi: 10.1104/pp.41.2.313.
Cycocel stimulated the activity of partial purified choline kinase from spinach or squash leaves, but it inhibited the activity of yeast choline kinase. The activity of different Cycocel analogs on plant growth corresponded to their stimulatory effect on the isolated choline kinase. Cycocel had no effect upon the activity of a plant phosphatase which hydrolyzed phosphorylcholine nor upon adenosine triphosphatase from wheat roots or leaves. Gibberellin A(3) inhibited choline kinase activity and reversed the stimulatory effect of Cycocel on the kinase. Total choline kinase activity per squash plant was not greatly increased by Cycocel treatment. However, on the basis of fresh weight, total kinase activity was increased by Cycocel treatment. Gibberellin A(3) partially reversed these increases. Treatment with Cycocel plus indoleacetic acid resulted in a large increase in choline kinase activity. The same distribution of tracer among phosphorylcholine, choline and betaine was observed when either phosphorylcholine-C(14) or choline-C(14) was fed to barley or wheat roots. Cycocel stimulated the incorporation of choline-C(14) into the insoluble fraction and into lipids. Cycocel inhibited phosphorylcholine uptake by roots. Thus Cycocel stimulated choline kinase activity and the utilization of choline-C(14). The effect of Cycocel upon kinase activity in vivo and in vitro was reversed by gibberellin A(3).
矮壮素刺激了菠菜或南瓜叶片部分纯化的胆碱激酶的活性，但抑制了酵母胆碱激酶的活性。不同矮壮素类似物对植物生长的作用与其对分离出的胆碱激酶的刺激作用相对应。矮壮素对水解磷酸胆碱的植物磷酸酶的活性以及小麦根或叶中的三磷酸腺苷酶均无影响。赤霉素A(3)抑制胆碱激酶活性，并逆转了矮壮素对该激酶的刺激作用。经矮壮素处理后，每株南瓜的总胆碱激酶活性并未大幅增加。然而，以鲜重计，经矮壮素处理后总激酶活性增加。赤霉素A(3)部分逆转了这些增加。用矮壮素加吲哚乙酸处理导致胆碱激酶活性大幅增加。当向大麦或小麦根饲喂磷酸胆碱-C(14)或胆碱-C(14)时，在磷酸胆碱、胆碱和甜菜碱之间观察到相同的示踪剂分布。矮壮素刺激胆碱-C(14)掺入不溶性部分和脂质中。矮壮素抑制根对磷酸胆碱的吸收。因此，矮壮素刺激胆碱激酶活性和胆碱-C(14)的利用。赤霉素A(3)逆转了矮壮素在体内和体外对激酶活性的影响。
