Characterization of His-Asp phosphorelay system in S.pombe and E. coli.

1.裂殖酵母中组氨酸-天冬氨酸磷酸化系统的研究发现：（1）在裂殖酵母基因组序列中发现的三种组氨酸激酶（HK）冗余地参与了G2/M期细胞周期调控。(2)HK分别在Spy 1和Mcs 4（HPt蛋白和反应调节剂）的上游工作。(3)Prrl是一种反应调节因子，参与减数分裂和氧化应激反应。在此过程中，HK可能作为氧化应激传感器参与其中.大肠杆菌His-Asp磷酸化系统的特性研究结果发现：（1）大肠杆菌中存在唯一的HPt蛋白;大肠杆菌YojN作为RcsC（HK）和RcsB（反应调节剂）之间的磷酸介体发挥作用，参与胶囊合成。(2)对大肠杆菌双组分调控系统突变体的微阵列分析表明，His-Asp磷酸化系统之间可能存在功能性相互作用（如串扰）。杆菌在这个分析中，我发现细胞的功能，如RpoS调节子和趋化性，受到多个His-Asp磷酸系统的影响。

1. Characterization of His-Asp phosphorelay system in fission yeastI found that :(1) Three histidine kinases (HK) found in that genome sequence of fission yeast are redundantly involved in the G2/M cell cycle control.(2) The HKs work upstream of Spy1 and Mcs4, the HPt protein and response regulator, respectively.(3) The Prrl, a response regulator, is involved in both meiosis and oxidative stress response. In this process, the HKs may be involved as oxidative stress sensors.2. Characterization of His-Asp phosphorelay system in E. coli.I found that :(1) A sole HPt protein in E. coli, YojN, functions as a phosphate mediator between RcsC (HK) and RcsB (response regulator) that is involved in the capsule synthesis.(2) There may be functional interactions (such as cross talk) among His-Asp phosphorelay systems based on the microarray analysis of all two-component regulatory system mutants of E. coli. In this analysis, I found the cellular functions, such as RpoS regulon and chemotaxis, are affected by multiple His-Asp phoshorelay systems.