植物光调蛋白激酶PPKs作用机制的研究进展

蛋白激酶(Protein kinases)又称蛋白质磷酸化酶,能够催化蛋白质分子中丝氨酸(Ser)、苏氨酸(Thr)及酪氨酸(Tyr)残基的磷酸化反应。Ⅰ型酪蛋白激酶(casein kinaseⅠ,CK1)是一类Ser/Thr蛋白激酶,从酵母到哺乳动物中都非常保守。近期研究发现,拟南芥中存在一类蛋白激酶能够在光下特异催化重要光受体及光信号蛋白的磷酸化,故将其命名为光调蛋白激酶(photoregulatory protein kinases,PPKs)。通过序列分析发现,PPKs与Ⅰ型酪蛋白激酶同源,但在功能和结构上都有别于Ⅰ型酪蛋白激酶。拟南芥中,PPK家族主要由4个成员组成:PPK1、PPK2、PPK3和PPK4。PPKs广泛参与多种植物生理过程,在调节植物生长发育中发挥重要作用。本研究对拟南芥蛋白激酶PPKs信号转导途径的相关研究进行探讨,旨在总结目前关于PPKs调控植物生长发育分子机制的认识。

Research Progress of the Mechanism of Photoregulatory Protein Kinases in Plant

Protein kinases,also known as protein phosphorylases,are enzymes that catalyze the phosphorylation at serine,threonine and tyrosine residues in protein molecules.Casein KinaseⅠ(CK1)is a class of Ser/Thr protein kinases that are highly conserved from yeast to mammals.Recent studies in Arabidopsis have identified a group of protein kinases which specifically catalyze the light-dependent phosphorylation of important photoreceptors and light signaling proteins.Therefore,they are names as photoregulatory protein kinases(PPKs).Sequence analysis reveals that PPKs share similarity with CK1,but with different protein structures and physiological activities.In Arabidopsis,PPK family includes 4 members,namely PPK1,PPK2,PPK3 and PPK4.PPKs are reported to involve in various plant physiological processes and play pivotal roles in regulating plant growth and development.In this review,we discuss the recent studies regarding the roles of PPKs in different cellular signaling pathways,with the aim to summarize the current knowledge of molecular mechanisms through which PPKs regulate plant growth and development.