拟南芥反应调节因子研究进展

Recent Advances on the Response Regulators in Arabidopsis thaliana

反应调节因子是His_Asp磷酸转移信号传导途径的重要组分。它通过在保守的Asp残基上接受由感受器转移而来的磷酸基团对下游基因进行调控 ,以对环境刺激作出反应。在高等植物拟南芥中已经发现 1 4种反应调节因子 ,它们可分为A ,B两种亚型。在结构上 ,B亚型反应调节因子的B盒序列和较长的C末端延伸使其具有转录因子的作用 ;在表达特性上 ,A亚型反应调节因子的转录受细胞分裂素和硝酸盐诱导 ;在生化特性上 ,A亚型反应调节因子具有磷酸化酶活性 。

Response regulator is a very important component in His_Asp phosphorelay signal transduction pathway. A given response regulator controls the downstream genes by acquiring a phosphoryl group from the sensor to its conserved aspartate residue in response to environmental stimuli. 14 members of the response regulators, which can be classified into two distinct subtypes, have been discovered in the higher plant Arabidopsis thaliana . In aspect of structure design, the type_B may serve as transcription factors because of the containing of B_motif and the relatively large C_terminal extension. The expression profile of type_A response regulators that are cytokinin_ and nitrate_inducible is also different from that of type_B. In aspect of biochemical properties, type_A response regulators appear to have a strong phosphohistidine phosphatase activity while those belonging to type_B may function as phosphodonor for AHPs.