细胞分裂素的生物合成、受体和信号转导的研究进展

Research Progress of the Biosynthesis,Receptor of Cytokinins and Cytokinin-Signal Transduction

细胞分裂素在调节植物生长发育过程中起着重要作用,如促进细胞分裂、芽分生组织的生长、形成次生代谢组织、延缓叶片衰老、抑制根的生长和分枝、在种子萌发和逆境应答中起重要的作用。在过去的10年,以模式植物拟南芥为材料,在细胞分裂素的生物合成、受体、信号转导等以及分子机理研究方面取得了显著的进步。细胞分裂素的生物合成主要通过AMP、ATP/ADP途径;细胞分裂素的受体主要有CRE1/WOL/AHK4、AHK2和AHK3。细胞分裂素的信号转导通过组氨酸到天冬氨酸的磷酸传递,包括磷酸传递、应答调节蛋白和二元组分体系。

Cytokinins are essential regulators of numerous plant growth and development processes.It stimulates the formation and activity of shoot meristems,is able to establish sink tissues,retard leaf senescence,inhibit root growth and branching,and plays a role in seed ger-mination and stress responses.During the past ten years,remarkable progress has been made to our understanding on the cytokinin biosynthesis,receptor and signal transduction,mainly using Arabidopsis thaliana as a model system.Biosynthetic pathways of cytokinins are mainly AMP pathway,ATP/ADP pathway.Arabidopsis thaliana possesses three cytokinin receptors： CRE1/WOL/AHK4,AHK2 and AHK3.Evidence has been provided that downstream signaling is transduced through a His-to-Asp phosphorelay involving phosphor transmitter and response regulator proteins,typical of two-component systems.