摘要：Protein kinases from rice embryos and leaves were identified, and the manner in which they are affected by plant hormones and light was studied. Ca2+-dependent protein kinase activity in embryos increased in early seedlings, but was inhibited during incubation in the presence of abscisic acid for 2 d. Ca2+-dependent protein kinase activity in leaves increased in the presence of gibberelline for 7 d. Ca2+- and phosphatidylserine (PS)-dependent protein kinase activity was found primarily in the cytosol fraction of rice leaves. In the dark, this Ca2+- and PS-dependent protein kinase activity could be detected in the membrane fraction of etiolated shoots. Protein kinases appear likely to regulate plant growth through protein phosphorylation.
